Referee Chat Blog

Discussions about how referees affect scoring by both teams

2012-01-18T23:39:00.003-05:00

Great post at Basketball Prospectus Unfiltered about the effects of NBA referees on how many points per possessions teams will score.

http://www.basketballprospectus.com/unfiltered/?p=815

I have been doing similar analysis for how a specific NFL referee crew might have an effect on how many points are scored per game.

The hypothesis for the NBA and NFL analysis is that some referees will favor scoring points for the home and visiting teams. This is a logical hypothesis because just as some umpires in baseball have a small strike zone (making it harder for the pitcher to strike out batters), maybe some NBA referees call many fouls against the defense (making it harder for the defense to stop the offense) and maybe some NFL referees call more defensive pass interference penalties than others (making it harder for the defense to stop the offense).

The idea is that if a referee is equally helpful to the offense of both teams, then the referee might not be intentionally trying to influence the result of the game, but just that different people call games a little differently. Tracking referee performance may be the next level of analyzing the game -- and it is disappointing that sports analysts don't spend more time on it.

If only sports analysts spent more time on it, fans might get more insight into the games and one day I might get a little publicity for referee analysis. Nothing wrong with a little attention, right?

Open discussion of January 2012 NFL playoff referees

2012-01-17T23:49:00.002-05:00

I've taken a little break from crunching numbers about NFL referees this season, but let me start an open discussion about NFL referees and the 2011 playoffs (the ones in January 2012).

For starters, what do people think about how Bill Leavy in a video review (challenged by the New York Giants) let stand the ruling on the field that Green Bay Packers receiver Greg Jennings was down before losing the ball, so it was not a fumble? (The Giants won the game despite the call, so the call didn't change the result of the game.)

The NFL has stated that:

Rule 7, Section 2, Article 1 of the NFL Rule Book (page 35) states: ‘An official shall declare the ball dead and the down ended: (a) when a runner is contacted by a defensive player and touches the ground with any part of his body other than his hands or feet. So by rule, if Jennings’ calf was on the ground prior to the ball coming loose, he is down by contact. Contrary to what was suggested during the game, there is no need for the runner’s knee to be on the ground.

Rule 15, Section 9 of the Rule Book (page 98) governs instant replay reviews and states: ‘All Replay Reviews will be conducted by the Referee on a field-level monitor after consultation with the other covering official(s), prior to review. A decision will be reversed only when the Referee has indisputable visual evidence available to him that warrants the change.'

Referee Bill Leavy conducted the instant replay video review and determined that there was no indisputable visual evidence to warrant reversing the on-field ruling of down by contact. As a result, the ruling on the field stood.

What do people think? Was the replay clear or not?

Feel free to comment on other controversial referee calls during the January 2012 playoff games, also. I am pretty perplexed about Bill Leavy's decision though and would like people's thoughts!

Referee Crews Influence Games Unintentionally To Different Degrees

2010-08-21T09:00:00.000-05:00

Much of our statistical analysis of referees is based on an assumption that different referee crews will influence games in different ways. Perhaps some referee crews tend to call penalties more strictly against both defenses so they wind up with more penalties per game and more points scored per game. By discussing differences among the referee crews, we are not saying that a specific crew is biased against a particular team. Or biased intentionally at all. Maybe they just have different characteristics (unintentionally). By looking at these differences, we can deepen our understanding of the game.

Judy Battista of The New York Times wrote an article on August 22, 2010 called Umpires Moved, And A Tactic Is Removed
http://www.nytimes.com/2010/08/22/sports/football/22umpire.html

She explained that some astute coaches tracked referee crews for specific characteristics about how the umpire would move on certain types of plays. Umpires were in the middle of the field and could essentially be used as an obstacle for the offense or defense to run around (or into) during plays.

It's more evidence that different referee crews influence games (unintentionally) in different ways. Back when the umpire always stood in the middle of the field, some referee crews opened up more options for the offense to succeed by using the umpire as an obstacle for defenders. So much so that astute coaches tracked differences among referee crews.

Can you think of some ways referee crews may influence games differently? Any theories you want to offer that someone can try to track during the season? It's easiest to make a theory that can be tested with standard statistics everyone already tracks (to avoid having to watch all the games yourself to track a new statistic!)

NFL Referees 2009 And How The Underdogs Did With Them

2010-02-07T09:58:00.000-05:00

One way to look at how normally a referee crew calls a game is to see whether home teams did extremely well when they were mega-favorites, somewhat well when they were slight favorites, poorly when they were slight-underdogs, and really badly when they were mega-underdogs. If the distribution of results has little correlation to the betting line, then it might be an indication that the referee crew calls games differently than most, so that the results are not that predictable. We looked at this in a recent posting.

A different way to look at how normally a referee crew calls a game is to see how well the favorites did, either as a raw won-loss percentage or against the spread. This approach ignores whether the home team performed easily or barely won (or beat the spread). It also ignores trying to find a correlation between the performance and by how much the team was a favorite.

Top and bottom referees for favorites' won-loss record in the 2009 regular season:
1. John Parry and Jeff Triplette (87%)
3. Don Carey and Bill Leavy (80%)
...
13. Carl Cheffers, Pete Morelli, Alberto Riveron, Gene Steratore (60%)
17. Jerome Boger (53%)
[The overall average was 69.5%, by the way.]

And the top and bottom for favorites against the spread:
1. Don Carey (80%)
2. John Parry (77%)
3. Bill Leavy, Walt Coleman, Ron Winter (60%)
...
13. Scott Green (38%)
14. Mike Carey and Terry McAulay (37%)
16. Ed Hochuli and Tony Corrente (33%)
[The overall average was 49.4%]

Scott Green is the referee for Super Bowl XLIV, the 2010 Super Bowl between the Colts and the Saints. How does he stack up (putting aside how he has an all-star crew rather than his regular crew)?

Favorites went 69% as a won-loss record, so he was 8th out of 17, or slightly good for favorites. This is right on the overall average of 69% for the year for all refs.

Favorites against the spread went 38%, so he was 13th out of 17th. Not good for favorites. This was way below the overall average of 49% for the year for all refs.

So a basic way to look at it would be to say the favorites (the Colts) have a 69% chance of winning and a 38% or 49% chance against the spread, depending on whether you focus on the season-long trend or Scott Green's trend.

But let's look at games where the betting line was 4-5 points. This will weed out games where there was an overwhelming favorite or one where the teams were virtually equal. For all referees, the favorites in those games went 56% as a won-loss rate and 48% against the spread. Not that favorable for the Colts.

As for Scott Green's regular season games, the results for the favorites W-L and ATS were: favored by 3 (0-1 W-L, 0-1 ATS), 3.5 (2-1 W-L, 2-1 ATS), 4.5 (1-0 W-L, 0-1 ATS), 5.5 (1-0 W-L, 1-0 ATS), 6 (3-0 W-L, 1-1-1 ATS). So when the point spread was between 3 and 6, favorites in Scott Green's games went 7-2 W-L and 4-4-1 ATS.

NFL Referees 2009 and Teams' Performance Compared To Expectations

2010-02-06T08:15:00.000-05:00

This piece looks at which referee crews in 2009 had a strong correlation between game results and what people expected for the game.

In a perfectly predictable crew, all things being equal, the home team's margin of victory or defeat would correlate almost perfectly with the betting line that for the most part tends to give an indication of the expected result for the game. (Of course, people who set the betting line are not solely focused on the expected result -- they are also focused on what betters' expectations of the results are, but we put that minor flaw to the side in this analysis because it is difficult to account for.)

Also for a perfectly predictable crew, all things being equal, the home team should win more often when it is heavily favored by the betting line and it should lose when it is the heavy underdog according to the betting line.

Is it good to be a perfectly predictable crew? Perhaps yes -- maybe being perfectly predictable means that the crew makes calls in the way that both teams expect, so they perform up to (or down to) their abilities. Meanwhile, a crew that has unpredictable results might reflect that they have unexpected interpretations of the rules and good teams cannot perform up to their expectations.

Let's take a look at two yardsticks -- correlation of the betting line to whether the home team won and correlation of the betting line to the home team's margin of victory (or loss).

Here are the rankings. The most predictable for 2009 is listed first:
1. Bill Leavy
2. John Parry
3. Don Carey
4. Jeff Triplette
5. Walt Coleman
...
13. Carl Cheffers
14. Ron Winter
15. Alberto Riveron
16. Pete Morelli
17. Scott Green

The Super Bowl referee for the Saints-Colts game is Scott Green, who had the least predictable game results in the regular season as correlated to the betting line. (Keep in mind the Super Bowl has an all-star crew so it is not Scott's usual crew.)

How did Scott Green rack up the least predictable results in the regular season? Let's take a look at some of the results compared to the betting line in his games.

You'd think that games where the home team is heavily favored, they would most likely win the game and vice-versa. But Denver as a home team was heavily favored (9.5 points) over Kansas City in week 17 but lost by 20 points. The Giants as a home team were heavily favored (9 points) over the Panthers in week 16 and lost by 32 points. Meanwhile, the Redskins as a visiting team were pretty favored (6.5 points) over the Lions in week 3 but lost by 5 points.

Other minor upsets were the Chargers as a home team was favored (3.5 points) over the Broncos in week 6 but lost by 11 points. The Steelers as a visiting team was favored (3 points) over the Bears in week 2 but lost by 3 points.

It turns out that the betting line did not help you predict which team would win the game. The upsets were randomly distributed along the betting line in his games.

For other referees, the home team won in the games where it was the most favored and its losses were clumped toward where it was the least favored. So the results correlated strongly to the pre-game betting line.

The specifics are that Scott Green had an -0.076 correlation between the betting line and the home team's margin of victory (17th out of 17 crews) and an 0.198 correlation between the betting line and whether the home team won (15th out of 17 crews).

If this holds up for the Super Bowl, then it suggests that the result of the game will not correlate well to the betting line. Perhaps teams do not perform in line with their expectations in Scott's games as much as they do in games with other crews...

NFL Referees for Super Bowl XLIV: February 2010 Saints-Colts

2010-02-06T07:32:00.000-05:00

Some analysis of the NFL referees for Super Bowl XLIV between the Saints and the Colts on February 7, 2010. Let's focus on the Super Bowl referee Scott Green, even though the Super Bowl has an all-star crew so Scott Green's regular season statistics (which are based on his usual crew) will not directly apply to the members of the Super Bowl crew.

Total penalties: 11th of 17 at 11.4 accepted penalties per game. Looking at the entire Super Bowl crew, none of them worked on the crews that had the 5 highest accepted penalties per game so my prediction is there will be a slightly below average number of penalties in the Super Bowl.

Total penalty yards: 8th of 17 at 99 penalty yards per game. Looking at the entire crew, it trends toward a lower number of penalty yards per game. Other than Scott Green, they were 3rd, 11th, 12th, 14th, 15th, and 17th out of 17.

Yards per penalty: 3rd of 17 at 8.7 yards per penalty. My prediction is there could be some high-yardage penalties, although not too many penalties. Other than Scott Green, the crew was 1st, 5th, 7th, 11th, 13th, and 15th out of 17.

Total points scored: 3rd of 17 at 48.1 yards per game. Hard to tell if it would be high-scoring because Scott Green suggests it would be high-scoring at 3rd out of 17, but the crew is spread out having worked on crews that were 1st, 7th, 9th, 11th, 12th, and 14th out of 17 during the regular season in total points scored.

Points scored compared with the over-under: 3rd of 17 at +5.3 per game. Think of this as the adjusted total points scored, accounting for what people expected to be scored in the game. This is similar to total points scored but if you looked only at the referees and nothing else (a dangerous approach), I would tend to bet on the over for the game. The crew worked during the regular season on crews that were 1st, 7th, 8th, 11th, 12th, and 15th in the regular season.

Over/under percentage win with the over: 4th of 17 at 63%. Again, I would tend to bet on the over for this game if all you looked at was the referee crew. The working crew for the regular season was on the 1st, 6th, 7th, 11th, 14th, and 17th crews so it was quite evenly-distributed.

Home team win rate: 5th of 17 at 63%. But this probably is irrelevant because the Super Bowl does not really have a true home team. The other crew is widely distributed, having worked on the 1st, 3rd, 8th, 11th, 14th, and 15th crews in the regular season for home team win rate.

Super Bowl Referees for Super Bowl XLIV (Saints-Colts)

2010-02-06T07:21:00.003-05:00

We come to the Super Bowl and two difficulties in analyzing the referee crews.

First, it is an all-star mixture of officials who worked on different crews in the regular season. So we can't rely on the regular season data because they did not all work together and it is difficult to separate out what part of a crew's statistics depends on each crew member.

The breakdown is:
Referee: Scott Green
Umpire: Undrey Wash (Cheffers's crew)
Head Linesman: John McGrath (Corrente's crew)
Line Judge: Jeff Seeman (Steratore's crew)
Side Judge: Greg Meyer (Don Carey's crew)
Back Judge: Greg Steed (McAulay's crew)
Field Judge: Rob Vernatchi (Morelli's crew)

So, do we analyze this as if Scott Green will impose his will on the crew and check his statistics only? None of the crew members have worked together before, so it is a mixture of seven different crews. Should we average out those seven crews' regular season statistics?

The second difference is that there is no true home team in the Super Bowl. I think we throw out the statistics we have about how each crew treated the home team and visiting team in the regular season games. However, maybe the statistics about how they treated favorites and underdogs still is useful. For example, if underdogs did especially well with a referee in the regular season, maybe that referee calls games a little differently than most referees so that it is harder to predict the result, which would also be true in a Super Bowl.

Let's dig in to the statistics for Scott Green's regular season, even though he has different crew members in the Super Bowl...

AFC Conference Championship Referee: Tony Corrente (Jets-Colts Game)

2010-01-24T16:50:00.001-05:00

For the 2009 AFC Conference Championship game in the NFL playoffs, Tony Corrente is handling the game between the New York Jets and the Indianapolis Colts. Let's look at how Tony's crew did during the regular season compared to all 17 referee crews.

6th in total accepted penalties per game (12.6)
3rd in total accepted penalty yards per game (105) so they are not afraid to call penalties often
7th in average yards per penalty (8.3) so not necessarily the crew that would call big penalties the most often
16th in percent penalties called against the visiting team (46%) and penalty yards against the visiting team (44%), so seems favorable to the Jets on this point. (Walt Anderson was 17th.)
14th in total points (40.5) so might be a lower scoring game than people expect
15th in points compared with the over/under line (-3.6)
17th in over/under (the over only won 23% in the regular season)
14th in home win rate (47%) so another good sign for the Jets

Looks like Tony's crew calls a decent number of penalties and the games are lower scoring than people expect, both on average and for the over/under record during the season. Also, the home team did not do very well in the games he covered during the season (but as a warning, it's not clear if home-win rate is a statistic that correlates across seasons by referee).

Home teams went 6-9 against the spread in Tony's games during the regular season. Good sign for the Jets.

The Colts won in week 1 in one of Tony's games, beating the Jaguars 14-12 in a home game. The over/under line was around 45 so a bet on the under would have won. Also, the Colts were favored by 6.5 points, so the home team did not do as well as expected (despite still winning). The Jets did not play any games under Tony in 2009. So by track record, the Colts did not do that well in one of Tony's games but they have more experience with Tony's crew this season.

Of course, the key will be how the players play, not the referees -- but you can use these statistics to enhance your viewing experience. Post any comments, insights, or questions!

NFL Referee Statistics Before Week 17 of the 2009 NFL Season

2010-01-03T10:03:00.002-05:00

More data and saving time by not going through all the categories. Post a comment if you'd like a focus on any of the categories.

Here are NFL referee statistics to use in week 17 (for the games that are on Sunday, January 3, 2010) because it includes data through week 16 or games through December 28, 2009.

Home Team Win Rate (the much-watched rate that home teams win for particular referees) These are unadjusted numbers and I have not seen a correlation from season to season, so this might not be correlated to specific referees. But we can track it anyway...

Highest: Bill Leavy and Jeff Triplette (79%), Peter Morelli (64%)
Lowest: Walt Anderson (29%), Ed Hochuli (36%), Terry McAulay, Tony Corrente, Carl Cheffers, Jerome Boger (43%)

Total Points (adjusted and unadjusted). Unadjusted are raw total points. Adjusted compares the total points to the over/under line for the game.

Highest: Gene Steratore (52.3, +10.2), John Parry (49.4, +7.1), Mike Carey (46.8, +3.6)
Lowest: Jerome Boger (34.7, -8.7), Ron Winter (38.2, -5.0), Walt Anderson (39.7, -3.6)

Not much difference between the unadjusted raw total points and the total points per game when accounting for the over/under line for the game.

Over/under % for the season so far: Gene Steratore (79% win rate with the over) versus Tony Corrente and Jerome Boger (25% win rate with the over).

Data Dump of Selected Statistics -- ok, a short table of selected statistics, copy this into a spreadsheet and you can sort to your heart's content. Post a comment if you find certain details or details interesting. Or if you find interesting trends in your analysis!

Referee (sorted by last name), Total accepted penalties per game, Total penalty yards per game, Average penalty yards per penalty, Total points per game, Home team win rate.
Walt Anderson (13.9, 124, 8.9, 39.7, 29%)
Jerome Boger (13.3, 101, 7.6, 34.7, 43%)
Don Carey (10.6, 84, 8.0, 41.9, 57%)
Mike Carey (12.6, 104, 8.2, 45.8, 43%)
Carl Cheffers (11.4, 97, 8.5, 43.3, 43%)
Walt Coleman (12.1, 102, 8.4, 45.9, 53%)
Tony Corrente (12.8, 108, 8.4, 41.0, 43%)
Scott Green (11.5, 97, 8.4, 46.8, 47%)
Ed Hochuli (12.9, 104, 8.0, 43.0, 36%)
Bill Leavy (10.6, 82, 7.7, 39.9, 79%)
Terry McAulay (11.4, 95, 8.3, 41.1, 43%)
Peter Morelli (10.3, 92, 9.0, 41.0, 64%)
John Parry (12.4, 99, 8.0, 49.4, 50%)
Alberto Riveron (10.9, 92, 8.5, 42.3, 50%)
Gene Steratore (9.8, 79, 8.0, 52.3, 50%)
Jeff Triplette (13.1, 105, 8.0, 45.9, 79%)
Ron Winter (13.0, 106, 8.2, 38.2, 57%)

NFL Referee Statistics Before Week 14 of the 2009 Season (Through games of December 7, 2009)

2009-12-13T15:22:00.000-05:00

Back after a few busy weeks off-line. More data and saving time by not going through all the categories. Post a comment if you'd like a focus on any of the categories.

Here are NFL referee statistics to use in week 14 (for the games that started on December 10 , 2009 because it includes data through week 13, games through December 7, 2009). This does not include the games from December 10-13.

Home Team Win Rate (the much-watched rate that home teams win for particular referees) These are unadjusted numbers and I have not seen a correlation from season to season, so this might not be correlated to specific referees. But we can track it anyway...

Highest: Bill Leavy and Jeff Triplette (73%), Peter Morelli, John Parry, Ron Winter (64%)
Lowest: Ed Hochuli (33%), Walt Anderson (36%), Jerome Boger (42%)

Total Points (adjusted and unadjusted). Unadjusted are raw total points. Adjusted compares the total points to the over/under line for the game.

Highest: Gene Steratore (50.4, +8.5), John Parry (47.2, +4.7), Mike Carey (47.1, +4.1)
Lowest: Jerome Boger (34.7, -8.2); Walt Anderson (37.9, -6.2), Tony Corrente (39.9, -4.1)

Not much difference getween the unadjusted raw total points and the total points per game when accounting for the over/under line for the game.

Over/under % for the season so far: Gene Steratore (82% win rate with the over) versus Walt Anderson (18% win rate with the over). Even though Jerome Boger has a lower total points when averaged over the season, Jerome has a 29% win rate with the over so Walt Anderson's games are more consistently lower-scoring than people expect.

Data Dump of Selected Statistics -- ok, a short table of selected statistics, copy this into a spreadsheet and you can sort to your heart's content. Post a comment if you find certain details or details interesting. Or if you find interesting trends in your analysis!

Referee (sorted by last name), Total accepted penalties per game, Total penalty yards per game, Average penalty yards per penalty, Total points per game, Home team win rate.
Walt Anderson, 14.5, 133, 9.2, 37.9, 36%
Jerome Boger, 13.3, 102, 7.7, 34.7, 42%
Don Carey, 11.3, 86, 7.7, 41.3, 45%
Mike Carey, 11.8, 98, 8.3, 47.1, 55%
Carl Cheffers, 11.2, 98, 8.7, 43.8, 50%
Walt Coleman, 13.0, 109, 8.4, 45.8, 58%
Tony Corrente, 12.5, 100, 8.0, 39.9, 45%
Scott Green, 11.1, 96, 8.6, 46.8, 50%
Ed Hochuli, 13.5, 111, 8.2, 45.5, 33%
Bill Leavy, 10.6, 82, 7.7, 40.2, 73%
Terry McAulay, 11.7, 96, 8.2, 41.9, 55%
Peter Morelli, 9.7, 88, 9.0, 41.5, 64%
John Parry, 12.3, 100, 8.1, 47.2, 64%
Alberto Riveron, 11.0, 95, 8.6, 44.2, 55%
Gene Steratore, 10.3, 80, 7.7, 50.4, 55%
Jeff Triplette, 12.3, 95, 7.7, 45.6, 73%
Ron Winter, 14.1, 114, 8.1, 41.1, 64%

NFL Referee Statistics Before Week 10 (through Week 9, 11/9/09)

2009-11-14T08:24:00.001-05:00

More data, but saving time by not going through all the categories Post a comment if you'd like a focus on any of the categories.

Here are NFL referee statistics to use in week 10 (use it for games starting November 12, 2009 because it includes data through week 9, games through November 9, 2009). This does not include the Thursday game on November 12.

I've been looking at over/under rates for correlations. Initial analysis -- no clear correlation for every season to the very next season but looking into potential correlations over a broader time period and by comparing the first half and the second half of the same season.

This is current as of November 11, 2009.

Home Team Win Rate (the much-watched rate that home teams win for particular referees) These are unadjusted numbers and I have not seen a correlation from season to season, so this might not be correlated to specific referees. But we can track it anyway...

Highest: Mike Carey and Scott Green (75%); Bill Leavy, Terry McAulay, and Jeff Triplette (71%)
Lowest: Don Carey (25%); Ed Hochuli and Carl Cheffers (38%)

Total Points (adjusted and unadjusted). Unadjusted are raw total points. Adjusted compares the total points to the over/under line for the game.

Highest: Mike Carey (54.5, +10.1); John Parry (51.3, +9.6); Gene Steratore (49.1, +9.5)
Lowest: Jerome Boger (32.6, -10.1); Bill Leavy (37.1, -4.5); Walt Anderson (37.3, -6.6)

So Bill Leavy has lower scoring games but when you account for the over/under line, Walt Anderson averages lower than expected total points per game. But if you look for over/under rate, as opposed to averages over the season, the referees who more often have the "under" are Bill Leavy, Tony Corrente, and Walt Anderson (29%) with Jerome Boger and Peter Morelli right behind at (31%). On the high side, the top three in average total points are grouped at the top in over/under rate at 86-88%.

Data Dump of Selected Statistics -- ok, a short table of selected statistics, copy this into a spreadsheet and you can sort to your heart's content. Post a comment if you find certain details or details interesting. Or if you find interesting trends in your analysis!

Referee (sorted by last name), Total accepted penalties per game, Total penalty yards per game, Average penalty yards per penalty, Total points per game, Home team win rate.
Walt Anderson, 14.1, 126, 8.9, 37.3, 43%
Jerome Boger, 14.3, 107, 7.5, 32.6, 50%
Don Carey, 11.3, 89, 7.9, 42.3, 25%
Mike Carey, 11.1, 95, 8.6, 54.5, 75%
Carl Cheffers, 10.9, 91, 8.4, 45.6, 38%
Walt Coleman, 13.5, 104, 7.7, 44.4, 50%
Tony Corrente, 11.7, 94, 8.0, 39.9, 57%
Scott Green, 12.6, 106, 8.4, 45.3, 75%
Ed Hochuli, 13.8, 117, 8.5, 47.3, 38%
Bill Leavy, 11.1, 87, 7.8, 37.1, 71%
Terry McAulay, 11.6, 95, 8.2, 39.7, 71%
Peter Morelli, 10.9, 93, 8.6, 41.5, 63%
John Parry, 13.0, 105, 8.1, 51.3, 57%
Alberto Riveron, 10.6, 90, 8.5, 46.8, 63%
Gene Steratore, 10.0, 78, 7.8, 49.1, 57%
Jeff Triplette, 12.4, 98, 7.9, 47.3, 71%
Ron Winter, 14.6, 117, 8.0, 44.6, 63%

Over/Under and Home-Team Referee Statistics from 2008 to 2009

2009-11-01T08:00:00.002-05:00

Let's take a closer look at the over/under records for each referee who worked in the 2008 season and is now working in the 2009 NFL season.

We've charted out the over/under record for each referee in 2008 and 2009. Let's see if there is a correlation between how each one ranked in 2008 and how each one ranked in 2009 after the first 7 games of the season. There would be a strong correlation, for example, if the rankings in 2008 was the same as the ranking in 2009 (whoever had the best record for the over in 2008 also had the best record for the over in 2009).

However, the over/under correlation between 2008 and 2009 (after 7 games) is -0.213. That is a negative correlation, suggesting that if a referee had a great record for the over in 2008, the referee had a bad record for the over in 2009. That suggests perhaps the over/under is not so referee specific.

Next, we ran the same analysis in comparing the 2008 record for each referee and the 2009 record after 7 games if you always went with the home team when taking a position against the point spread (regardless of whether the home team was favored or the underdog).

The correlation for home team (against the spread) is even worse: -0.425. Maybe using this limited data, it is not suggesting that a particular referee is better for home teams across seasons against the spread.

To give you an idea how bad that correlation figure is, the figures between 2008 and 2009 so far are much higher for: total accepted penalties (0.574) and total accepted penalty yards (0.396).

Here are some examples on the over/under issue:
at the top:
Carl Cheffers: Over-2008 (73%) and Over-2009 so far (50%)
Bill Leavy: Over-2008 (67%) and Over-2009 so far (only 17%)

at the bottom:
Gene Steratore: Over-2008 (40%) and Over-2009 so far (a huge 100%)
Scott Green: Over-2008 (27%) and Over-2009 so far (57%)

Here are some examples on the home team against the spread:
at the top:
Alberto Riveron: Home Team ATS 2008 (63%) and Home Team ATS 2009 so far (50%)
Jerome Boger: 2008 (60%) and 2009 so far (only 14%)

at the bottom:
Scott Green: 2008 (33%) and 2009 so far (a huge 71%)
Gene Steratore: 2008 (33%) and 2009 so far (67%)
Ed Hochuli: 2008 (31%) and 2009 so far (33%)

Let's check in on this later in the season. If we see interesting correlation figures for other ways to analyze referees, we can post on it again on the blog.

NFL Referee Statistics Before Week 8 (before November 1, 2009)

2009-10-31T21:15:00.000-05:00

More data, but saving time by not going through all the categories like last time. Post a comment if you'd like a focus on any of the categories.

Here are NFL referee statistics to use in week 8 (use it for games starting November 1, 2009 because it includes data through week 7, games through October 26, 2009).

This is current as of October 31, 2009.

Home Team Win Rate (the much-watched rate that home teams win for particular referees) These are unadjusted numbers and I have not seen a correlation from season to season, so this might not be correlated to specific referees. But we can track it anyway...

Highest: Mike Carey (83%), Scott Green (71%), a bunch at 67%
Lowest: Ed Hochuli, Carl Cheffers, and Don Carey tied at 33%

Data Dump of Selected Statistics -- ok, a short table of selected statistics, copy this into a spreadsheet and you can sort to your heart's content. Post a comment if you find certain details or details interesting. Or if you find interesting trends in your analysis!

Referee (sorted by last name), Total accepted penalties per game, Total penalty yards per game, Average penalty yards per penalty, Total points per game, Home team win rate.
Walt Anderson, 14.5, 126, 8.7, 36.7, 50%
Jerome Boger, 14.7, 109, 7.4, 29.4, 43%
Don Carey, 12.2, 99, 8.1, 40.8, 33%
Mike Carey, 11.5, 95, 8.3, 56.2, 83%
Carl Cheffers, 10.8, 96, 8.8, 41.2, 33%
Walt Coleman, 12.5, 92, 7.3, 47.0, 50%
Tony Corrente, 12.2, 98, 8.0, 35.8, 67%
Scott Green, 12.6, 108, 8.6, 44.6, 71%
Ed Hochuli, 14.5, 124, 8.6, 44.0, 33%
Bill Leavy, 12.0, 95, 7.9, 35.8, 67%
Terry McAulay, 11.7, 100, 8.5, 39.7, 67%
Peter Morelli, 12.3, 108, 8.8, 37.2, 50%
John Parry, 12.7, 102, 8.1, 51.2, 50%
Alberto Riveron, 10.7, 89, 8.3, 52.3, 50%
Gene Steratore, 10.2, 77, 7.6, 50.5, 67%
Jeff Triplette, 11.8, 90, 7.7, 46.4, 60%
Ron Winter, 14.5, 116, 8.0, 47.0, 67%

NFL Referee Statistics before Week 7 (before October 25, 2009)

2009-10-24T07:00:00.000-05:00

Yet more data, crunched just for you. NFL referee statistics to use in week 7 (use it for games starting October 25, 2009 because it includes data through week 6, games through October 19, 2009).

Give me some feedback in the comments -- any of these categories you don't care about? Does you find the data dump at the end helpful or not worth it every week?

This is current as of October 20, 2009.

Total accepted penalties per game

Highest: Walt Anderson (15.6), Ron Winter (14.6), Ed Hochuli (14.5) [no changes from the previous week]
Lowest: Alberto Riveron (10), Mike Carey (10.2), Bill Leavy (10.8) [Carl Cheffers falls from 2nd to 4th]

Average yards per accepted penalty (this may help you figure out whether a specific crew calls a higher percentage of large-yardage penalties -- defense backs and wide receivers might be very interested in case this reflects pass interference calls downfield)

Highest: Peter Morelli (9.5), Alberto Riveron (8.9), Walt Anderson (8.9) [no changes]
Lowest: Walt Coleman (7.3), Jerome Boger (7.4),Jeff Triplette (7.7) [Boger falls from 1st to 2nd]

Total points scored -- raw (some referees tend to favor both teams' offenses rather than both teams' defenses, so more total points will be scored -- or do other things that tend to increase the total points scored). No adjustments for the teams playing.

Highest: Mike Carey (58.4), Alberto Riveron (54.6), Gene Steratore (53) [no changes]
Lowest: Jerome Boger (27.36), Walt Anderson (33), Bill Leavy (34.2) [no changes]

Total points scored -- adjusted (referees may tend to favor higher-scoring games more than others). These figures are adjusted by accommodating the over-under betting line, which is a pre-game prediction that takes account of the teams involved.

Highest: Mike Carey (+14.4), Gene Steratore (+12.7), Alberto Riveron (+12.7) [Steratore goes from 3rd to 2nd]
Lowest: Jerome Boger (-14.5), Walt Anderson (-10.2), Bill Leavy (-8.2) [Boger goes from 2nd to 1st]

Home Team Net points -- adjusted (perhaps some referees favor home teams more and the home teams do better than expected, using the pre-game betting line as an unofficial estimate of how well the home teams were expected to do)

Highest: Gene Steratore (+8.5), John Parry (+5.8), Scott Green (+5.7) [big changes with Steratore rocketing up to the top]
Lowest: Ed Hochuli (-7.1), Walt Anderson (-6.1), Jeff Triplette (-4.6) [much closer race and Triplette creeps into the top 3]

Home Team Win Rate (the much-watched rate that home teams win for particular referees) These are unadjusted numbers and I have not seen a correlation from season to season, so this might not be correlated to specific referees. But we can track it anyway...

Highest: Bill Leavy, Mike Carey, Gene Steratore, Terry McAulay (80%)
Lowest: Ed Hochuli (33%), Walt Anderson, Don Carey, Carl Cheffers (40%)

Data Dump of Selected Statistics -- ok, a short table of selected statistics, copy this into a spreadsheet and you can sort to your heart's content. Post a comment if you find certain details or details interesting. Or if you find interesting trends in your analysis!

Referee (sorted by last name), Total accepted penalties per game, Total penalty yards per game, Average penalty yards per penalty, Total points per game, Home team win rate.
Walt Anderson, 15.6, 138, 8.9, 33.0, 40%
Jerome Boger, 14.5, 107, 7.4, 27.3, 50%
Don Carey, 12.0, 97, 8.1, 42.2, 40%
Mike Carey, 10.2, 86, 8.4, 58.4, 80%
Carl Cheffers, 10.8, 90, 8.3, 39.8, 40%
Walt Coleman, 12.5, 92, 7.3, 47.0, 50%
Tony Corrente, 12.2, 98, 8.0, 35.8, 67%
Scott Green, 12.8, 113, 8.8, 42.3, 67%
Ed Hochuli, 14.5, 124, 8.6, 44.0, 33%
Bill Leavy, 10.8, 88, 8.2, 34.2, 80%
Terry McAulay, 11.6, 102, 8.8, 41.8, 80%
Peter Morelli, 11.6, 110, 9.5, 35.8, 60%
John Parry, 12.4, 106, 8.6, 45.4, 60%
Alberto Riveron, 10.0, 89, 8.9, 54.6, 60%
Gene Steratore, 11.2, 86, 7.7, 53.0, 80%
Jeff Triplette, 11.8, 90, 7.7, 46.4, 60%
Ron Winter, 14.6, 121, 8.3, 47.6, 60%

NFL after week 6: Over/Under And Referees

2009-10-22T07:00:00.001-05:00

After week 6 (through games of October 18), let's take a look at whether there is a correlation between NFL referees and the over/under result of the games.

I split up the season so far into two groups: the statistic for weeks 1-3 and the statistic for weeks 4-6. With this extremely limited data, let's see whether the distribution among the referees for weeks 1-3 have a correlation to the distribution for weeks 4-6.

The correlation for this limited data is 0.642. So there is a strong correlation with this very limited data. The referees who mainly had higher than expected scores in their games in weeks 1-3 for the most part also had high-scoring games in weeks 4-6. Those who had low-scoring games in weeks 1-3 kept up that trend in weeks 4-6.

Looking at this another way, if you bet that (a) the referees who had 100% over/under in weeks 1-3 would always be over for weeks 4-6 and (b) those who were 0% for weeks 1-3 would always be under in weeks 4-6, you would have gone 9-2! An 81% betting success rate over three weeks looks pretty good.

Maybe the people who set the over/under lines are not taking into account the referees in the game. Maybe this is a hidden advantage for those keeping track of it.

But watch out -- this analysis is based on only six weeks of games. Maybe it is just a statistical anomaly because of the small sample size. Or maybe there is a correlation in the early part of the season but referees have less influence over the points scored as a season progresses. Or maybe some referees will hear of this analysis and actively work to have less unconscious influence on the total points scored per game.

Post your comments about whether you think this is a statistical anomaly of no significance or if you suspect it might be a valid theory...

NFL Referee Over/Under Statistics (Week 6)

2009-10-18T08:15:00.003-05:00

Let's take a look at the over/under statistics for the NFL referees as of the beginning of week 6. (This means we compiled the statistics through the end of week 5, including games through October 12, 2009). This list is as of the morning of October 18, before today's games take place.

Over/under is a target number that a casino will set for the combined score of the teams that are playing the game. People have two choices -- to wager that the combined score will be larger than the target number or that the combined score will be lower. This operates as a rough estimate of the expected total number of points that will be scored in the game. (It is not an exact estimate because casinos try to set a target number where an equal number of bets will be placed on each side, so the casino is estimating the views of the people wagering on the contest rather than what the casino really thinks will happen.)

Let's take a look at the over/under statistics of referees. Is it possible that some referees have an unconscious tendency to favor the offense of both teams (perhaps a personal interpretation of the rules or tending to get the ball ready more quickly so there are more plays run per game)? If a referee favors the offense of both teams, the referee is not intentionally trying to help one team more than the other. It'd be like an umpire in a baseball game who happens to have a generous strike zone and calls it equally for both teams.

Here are the statistics through week 5:
Mike Carey, +13.4, 100%
Gene Steratore, 10.6, 100%
Alberto Riveron, 12.7, 80%
Ron Winter, 2.7, 80%
John Parry, 4.3, 75%
Terry McAulay, 4.0, 75%
Jeff Triplette, 3.6, 75%
Walt Coleman, 8.9, 60%
Don Carey, 0.3, 60%
Carl Cheffers, 0.8, 50%
Scott Green, -1.9, 40%
Ed Hochuli, -3.1, 40%
Jerome Boger, -12.9, 30%
Peter Morelli, -2.9, 25%
Tony Corrente, -5.2, 20%
Bill Leavy, -10.0, 0%
Walt Anderson, -13.6, 0%

What does this table show? Referee name then average points greater than the over/under line, then the percent of games where the over would win. (We set a push at 50% for that game.)

Using a guess at which referee is doing which game, let's make some over/under predictions for this week. Wager on the over for the Baltimore Ravens-Minnesota Vikings game and the Tennessee Titans-New England Patriots game. Wager on the under for the Houston Texans-Cincinnati Bengals game and the Cleveland Browns-Pittsburgh Steelers game.

If you play fantasy football, then if you are on the fence about whether to play an offensive player on the Ravens, Vikings, Titans, or Patriots rather than someone on the Texans, Bengals, Browns, or Steelers, you might account for the referee and tend for the ones playing in games where referees have had high-scoring games in the first 5 weeks of the NFL season...

And if it turns out there is no correlation between the referee and the points scored, all this analysis will be worthless! Try this out at your own risk!

Update: let's see how our experiment worked (or didn't):

Ravens-Vikings: recommended the over. Yes, the over won.
Titans-Patriots: recommended the over. Yes, the over won big-time.
Texans-Bengals: recommended the under. Yes, the under won, barely.
Browns-Steelers: recommended the under. Nope, the under lost.

So our small experiment went 3-1. If you bet the house, you still have a place to live in tonight. Post your comments on whether you think this is a theory worth exploring in the coming weeks or just a bizarre experiment with too small of a sample size.

NFL Referee Statistics Before Week 6 (as of October 17)

2009-10-17T10:32:00.000-05:00

More data! NFL referee statistics to use in week 6 (use it for games starting October 18, 2009 because it includes data through week 5, games through October 12, 2009).

This is current as of October 12, 2009.

Total accepted penalties per game

Highest: Walt Anderson (17.5), Ron Winter (14.6), Ed Hochuli (14.4)
Lowest: Alberto Riveron (10), Carl Cheffers (10.3), Mike Carey (10.5)

Highest: Peter Morelli (9.6), Alberto Riveron (8.9), Walt Anderson (8.8)
Lowest: Jerome Boger (6.9), Walt Coleman (7.4), Gene Steratore (7.6)

Highest: Mike Carey (57), Alberto Riveron (54.6), Gene Steratore (51.5)
Lowest: Jerome Boger (27.6), Walt Anderson (31), Bill Leavy (31.5)

Highest: Mike Carey (+13.4), Alberto Riveron (+12.7), Gene Steratore (+10.6)
Lowest: Walt Anderson (-13.6), Jerome Boger (-12.9), Bill Leavy (-10.8)

Highest: Scott Green (+9.7), Carl Cheffers (+8.8), John Parry (+8.3)
Lowest: Ed Hochuli (-12), Walt Anderson (-7.4), Jerome Boger (-6.5)

Highest: Bill Leavy and Mike Carey (100%), Scott Green and Tony Corrente (80%)
Lowest: Ed Hochuli (20%), Walt Anderson (25%), Jerome Boger and Don Carey (40%)

Data Dump of Selected Statistics -- ok, a short table of selected statistics, copy this into a spreadsheet and you can sort to your heart's content. Post a comment if you find certain details or details interesting. Or if you find interesting trends in your analysis!

Referee (sorted by last name), Total accepted penalties per game, Total penalty yards per game, Average penalty yards per penalty, Total points per game, Home team win rate.
Walt Anderson, 17.5, 154, 8.80, 31.0, 25%
Jerome Boger, 13.6, 94, 6.93, 27.6, 40%
Don Carey, 12.0, 97, 8.07, 42.2, 40%
Mike Carey, 10.5, 85, 8.07, 57.0, 100%
Carl Cheffers, 10.3, 80, 7.76, 42.3, 50%
Walt Coleman, 10.6, 78, 7.38, 50.6, 60%
Tony Corrente, 12.6, 99, 7.89, 39.0, 80%
Scott Green, 13.8, 117, 8.49, 39.4, 80%
Ed Hochuli, 14.4, 116, 8.07, 37.8, 20%
Bill Leavy, 10.8, 84, 7.84, 31.5, 100%
Terry McAulay, 10.8, 93, 8.67, 43.5, 75%
Peter Morelli, 12.8, 122, 9.59, 39.3, 50%
John Parry, 13.5, 116, 8.56, 44.5, 75%
Alberto Riveron, 10.0, 89, 8.88, 54.6, 60%
Gene Steratore, 11.0, 84, 7.64, 51.5, 75%
Jeff Triplette, 12.5, 96, 7.70, 47.3, 50%
Ron Winter, 14.6, 121, 8.26, 47.6, 60%

NFL Referee Statistics before Week 5 (October 11, 2009)

2009-10-11T08:20:00.003-05:00

Another week, more data -- NFL referee statistics to use in week 5 (use it for games starting October 11, 2009 because it includes data through week 4, games through October 5, 2009).

This is current as of October 6, 2009. [Note, made some corrections to Walt Anderson's data on 10/13/09 -- thanks to 81Trucolors for pointing this out!]

Remember, all of these statistics are not proof that any NFL referee is cheating. It is perfectly normal that some referees call a game slightly differently than others. This can be an unconscious tendency that differs between referees, not necessarily any intentional bias. It should be perfectly fine to discuss the variations between referees -- I am not questioning whether the referees are cheating! Also, NFL teams track referee tendencies already, so why not help NFL fans with the same tracking...

Total accepted penalties per game

Highest: Walt Anderson (18), Ed Hochuli (15), Scott Green (14.8)
Lowest: Alberto Riveron (9), Terry McAulay (9.7), Mike Carey (10.5)

Highest: Walt Anderson (8.9), Peter Morelli (8.77), Ron Winter (8.74)
Lowest: Jerome Boger (8.06), Carl Cheffers (7.41), Don Carey (7.46)

Highest: Mike Carey (57), Walt Coleman (54), Alberto Riveron (53.8)
Lowest: Walt Anderson (28), Bill Leavy (31.5), Jerome Boger (32.3)

Highest: Mike Carey (+15.8), Gene Steratore (+14.6), Alberto Riveron (+11.6). So Mike Carey comes out the highest, while Gene Steratore goes up from 4th on the raw list to 2nd on the adjusted list.
Lowest: Peter Morelli (-8.8), Walt Anderson (-8) [corrected 10/13], Tony Corrente (-5.8). Tony Corrente moved from 6th lowest on the raw list to 3rd lowest on the adjusted list. Peter Morelli moved from 4th to 1st.

Highest: Tony Corrente (+7.4), Carl Cheffers (+6.7), Terry McAulay (+5.5)
Lowest: Jeff Triplette (-21), Ed Hochuli (-16.6), Jerome Boger (-14.9)

Highest: Bill Leavy and Mike Carey (100%), Tony Corrente, Ron Winter, Scott Green, Gene Steratore (75%)
Lowest: Ed Hochuli (25%), Walt Anderson [corrected 10/13], Jeff Triplette, Carl Cheffers (33%)

Jerome Boger, 13.0, 92, 7.06, 32.3, 50%

Don Carey, 12.0, 90, 7.46, 40.8, 50%

Mike Carey, 10.5, 85, 8.07, 57.0, 100%

Carl Cheffers, 11.3, 84, 7.41, 44.0, 33%

Walt Coleman, 11.0, 86, 7.82, 54.0, 50%

Tony Corrente, 12.5, 101, 8.08, 36.5, 75%

Scott Green, 14.8, 126, 8.53, 39.0, 75%

Ed Hochuli, 15.0, 114, 7.60, 35.3, 25%

Bill Leavy, 10.8, 84, 7.84, 31.5, 100%

Terry McAulay, 9.7, 77, 8.00, 42.3, 67%

Peter Morelli, 11.7, 102, 8.77, 34.0, 67%

John Parry, 14.3, 119, 8.33, 42.3, 67%

Alberto Riveron, 9.0, 69, 7.67, 53.8, 50%

Gene Steratore, 11.0, 84, 7.64, 51.5, 75%

Jeff Triplette, 11.0, 90, 8.18, 46.0, 33%

Ron Winter, 13.3, 116, 8.74, 48.0, 75%

2009 NFL Referee Statistics for Week 4 (through October 3, 2009)

2009-10-04T10:56:00.000-05:00

Our first analysis of the statistics for NFL referees in the 2009 NFL season. This is our week 4 report, meaning that we compile the statistics from week 1 through week 3, through the end of September 2009. Use this to think about the week 4 games (starting October 4).

The numbers for the first three weeks mean that some referees have only done 2 games so far. This is a very small sample size and I am not going to try to draw too many conclusions from them. But post a comment if you have some questions or ideas -- some basic numbers:

Total accepted penalties (correlation to home team win rate: -0.358)

most: Walt Anderson (18.5)
Ed Hochuli (17)
Scott Green (16)
least: Alberto Riveron (8.7)
Mike Carey and Terry McAulay (9.7 each)

Percent penalties called against the visiting team: (correlation to home team win rate: -0.051)

most: Peter Morelli (60%)
Jeff Triplette (58%)
John Parry (56%)
least: Tony Corrente (35%)
Don Carey (42%)
Gene Steratore (43%)

Total points scored: (correlation to home team win rate: 0.162)

most: Mike Carey (59)
Alberto Riveron (53.7)
Gene Steratore (51)
least: Walt Anderson (28.5)
Jerome Boger (28.7)
Bill Leavy (30.7)

Total points scored compared to the game's expected points (using the betting over/under line). Correlation to home team rate: 0.266

most: Mike Carey (+15.3) [tops on both lists]
Gene Steratore (+11.8) [3rd on raw points scored, 2nd on this list]
Alberto Riveron (+9.8) [2nd on raw points, 3rd on this list]
least: Walt Anderson (-17) [the least ones are in the same order in raw points and this list]
Jerome Boger (-10.7)
Bill Leavy (-9)

Home team win rate:

Mike Carey, Scott Green, Bill Leavy (100%)
Carl Cheffers, Ed Hochuli, Jeff Triplette, Walt Anderson (0%)

And let's go to the tiebreaker -- the average points spread for home teams for these referees. Of the ones where the home team won each game, Scott Green is the best because home teams in his games were favored by only 1.2 points (5 for Mike Carey, 6 for Bill Leavy).

Of the ones where the home team lost each game, Ed Hochuli is best for visiting teams so far because in his games, home teams were favored by 4.2 points (-2.3 for Walt Anderson, -3.5 for Jeff Triplette, and -10 for Carl Cheffers).

Unusual correlation after very limited data: hmmm, some strange correlations with this very limited data. The correlation of the over-under line to the home team win rate is pretty negative, suggesting that when you expect a low-scoring game, this is very good for the home team generally. Looking game by game so far, the over-under line has an -0.237 correlation to the home team win rate and a -0.269 correlation to the amount of points that the home team scores more than the visiting team. Let's look at this again during the year...

Referee Roster Changes from 2008 to 2009

2009-10-04T10:25:00.000-05:00

We start to look at the new NFL season and wonder which referees from the 2008 season are not head referees in the 2009 season. There are retirements every year, so changes are nothing unusual.

Let's take a look -- Bill Carollo (listed as William Carollo on the game reports) retired at the end of 2008 and became the director of officiating for the Big Ten Conference. Meanwhile, Don Carey is a new head referee in 2009 and he is the brother of NFL referee Mike Carey. So now we can't log the referees by last name -- gotta get the first names to distinguish the Carey brothers... let's see how the statistics look as the year progresses.

Refchat Index: Analyzing Strength of Schedule for the 2009 NFL Season

2009-09-13T08:00:00.000-05:00

In our last blog posting, we explained that the visiting team's offense has a surprisingly smaller impact on the result of the game (both when you account for scoring margin and when you focus only on which team won) than either the visiting team's defense, the home team's defense, or the home team's offense.

We can use this to make an adjustment in predicting a game or analyzing which team has a tougher schedule. We'll make an adjustment that puts the most weight on the home team's offense, a good amount of weight on each team's defense, and a small weight on the visiting team's offense. Let's call this the Refchat Index.

Let's look at which teams have the strongest and weakest schedules in the 2009 NFL season based on how their opponents did in 2008. We'll focus first on the scoring margin for each team. Next, we'll roll out the Refchat Index and analyze the schedules using our weighted analysis.

Under raw scoring margin, the teams with the easiest schedules based on how the opponents fared in 2008 are: Green Bay Packers, Arizona Cardinals, Minnesota Vikings, Baltimore Ravens, and the Seattle Seahawks. The teams with the hardest schedules based on raw 2008 scoring margin are: Miami Dolphins, Carolina Panthers, Tampa Bay Bucs, Atlanta Falcons, and the New England Patriots.

But using the Refchat Index, the teams with the easiest 2009 NFL schedules using 2008 data are: Arizona Cardinals, Green Bay Packers, Pittsburgh Steelers, St. Louis Rams, and the Chicago Bears. The teams with the hardest schedules are: Carolina Panthers, Miami Dolphins, Atlanta Falcons, New England Patriots, and the Tampa Bay Bucs.

Comparing the Refchat Index to the raw scoring data, the teams whose schedules are much easier using the Refchat Index are: St. Louis Rams (4th easiest rather than 11th easiest), Pittsburgh Steelers (3rd easiest rather than 7th easiest), and the Washington Redskins (17th easiest rather than 21st easiest).

The teams whose schedules look much harder when you apply the Refchat Index are: Cincinnati Bengals (21st easiest rather than 14th easiest), Detroit Lions (18th rather than 13th), and the Baltimore Ravens (9th rather than 4th).

So if you use the rough yardstick of how opponents did in 2008, then the Refchat Index suggests that the Rams, Steelers, and Redskins may do better than most people predict (although the Redskins still have a tough schedule) and that the Bengals, Lions, and Ravens may do worse than most people predict (although the Ravens still have an easier than average schedule).

Of course, a big problem with this analysis is that NFL teams do not stay consistent from year to year, but if you want an overview of the upcoming season, this is how the Refchat Index would influence the analysis.

Predicting NFL Games: Visiting Team's Offenses Are Overrated

2009-09-12T17:00:00.000-05:00

Although we focus on referee statistics, as long as we are logging data about the 2008 NFL season, we can look at other pieces of information, such as how to predict the results of NFL games regardless of what referee is covering the game.

Looking over the 2008 NFL season, we come up with a theory -- the strength of the visiting team's offense is overrated. You might take advantage of this by downgrading the importance of the visiting team's offense. If the visiting team has a great offense, that team might be a bit overrated. If the visiting team has a terrible offense, that team might be a bit underrated for that game.

Let's take a look at the 2008 NFL season. If we use points scored by the offense and points given up by the defense, it gives us a rough way to put a value on how good the team's offense and defense are. This rough statistic is not exact -- for example, it doesn't account for the strength of schedule -- but over the course of the 16-game season perhaps it evens out to a good degree.

We took a look at the correlation of the offense and the defense of the visiting teams and of the home teams to the final score and then to which team won (regardless of the scoring margin). In each case, we found that the biggest influence is the home team's offense. A bit further back is the strenth of each team's defense. And much further back is the strength of the visiting team's defense.

For example, in the 2008 NFL season, the correlation to the scoring margin was:

Home team's offense (0.375)
Home team's defense (0.276)
Visiting team's defense (0.207)
Visiting team's offense (0.128)

There is a similar disparity when you compare the teams' offense and defense to the game result (ignoring scoring margin).

So the new theory is: the Visiting Team's Offense Is Overrated.

And you can take advantage of this by adjusting the traditional predictions when the visiting team's offense is particularly strong or particularly weak.

We can use this theory to modify other analyses, such as strength of schedule. We'll do that in another posting.

Any Requests for the 2009 NFL Season?

2009-09-04T09:00:00.000-05:00

Any requests or ideas for what to try to track for the upcoming 2009 NFL season for referees and their statistics?

With limited time, I can't track a ton of statistics, but I will try to track what I hope will be the most interesting and useful statistics for analysis. Let me know what ideas you have -- if I don't have time, maybe some other reader will pick up on your ideas.

Tracking referee statistics really becomes interesting during the regular season, not beforehand. The problem with looking at referee statistics while planning your fantasy football draft or projecting a team's season is that the NFL does not release the upcoming referee schedule for the year. So even if it turns out that your favorite running back will have an offense-favorable referee schedule, you won't know that when it's time to do your fantasy football draft or make your projections for the year.

When the season starts, I'll discuss some non-referee statistical analysis I've done on the past season, including the trend that the visiting team's offense is not as important for predicting the result of the game as other factors.

Nice Story on NFL Referee Ed Hochuli

2009-05-12T08:00:00.001-05:00

Elizabeth Merrill has a great off-season story about NFL referee Ed Hochuli at espn.com for Outside the Lines.
http://sports.espn.go.com/espn/eticket/story?page=090507/hochuli

At this site, I try to focus on NFL referee statistics as a way to analyze referees' performance, especially to look for trends and tendencies that distinguish referee crews from each other. I'd like there to be much more discussion about tendencies by referees without accusing referees of cheating or trying to make bad calls. It is difficult to use statistics to figure out whether a referee is having a bad day and making mistakes or intentionally trying to affect the result.

Instead, it might be more productive to look at all of the unconscious tendencies that distinguish referees from each other, such as whether some referees are sticklers for the rules or call less penalties (often doing so even-handedly by being stricter or more lenient for both teams in the game). Or perhaps some referees are more friendly to high-scoring games than more defensive-minded referees. I'd like to comb through the statistics to figure this out -- but not to accuse the referees of intentionally trying to change the result.

Referees, Criticisms, and Apologies Outside the NFL

2009-05-10T08:45:00.000-05:00

One of my main points in analyzing NFL referee statistics is that journalists should spend more time criticizing NFL referees and commenting on their tendencies along with their performance during a game. It's possible to focus on a referee's tendencies without suggesting that a referee is trying to swing the game in one team's favor. For example, a referee might have an unconscious bias toward home teams because they are influenced by lots of cheering fans, even though they honestly attempt to block out the home crowd.

Or even more innocently, some referees are sticklers with the rule book (and call more penalties), while others are more lenient and let both teams get away with more. That doesn't mean a referee is trying to influence the game, it's just the unconscious tendency of referees.

Let's take a look at two examples outside of the NFL.

In the game between the Dallas Mavericks and the Denver Nuggets on May 9, 2009, Antoine Wright fouled Carmelo Anthony with a few seconds left in the fourth quarter but by mistake, NBA referee Mark Wunderlich did not make the foul call. It had a major effect on the game and within a few hours after it ended, the NBA admitted that the ref had made a mistake. I think it's a good move by the NBA to acknowledge a mistake, good that the journalists were already focused on the mistake, and too bad the NBA still has a gag rule that stops players and coaches (including Mark Cuban, who often has interesting analysis and ideas) from saying anything about what everyone was focused on.

In the game between Chelsea and Barcelona in the UEFA Champions League semifinal on May 6, 2009, referee Tom Henning Ovrebo made several controversial calls, especially a red card for Abidal, no penalty for a foul on Alves on Malouda, no penalty when Toure tugged on Drogba's shirt, no penalty when Anelka's flick-on is stopped by Pique's arm, and no penalty when Ballack shoots the ball and hits the shoulder or arm of Eto'o. There's no established way for UEFA to make a report on the referee's decisions and either stand by them or concede that he made a human error at some point. It's good that journalists are focused on the controversial calls and it is also good that UEFA does not have a gag rule so players and coaches can express their opinions (though hopefully not like Drogba did to a live audience at the end of the match!) Oh, and everyone needs to protect referees from death threats, also.

Looks like people have a way to go to reach intelligent, respectful analysis of referee performance. I will try to move in that direction with some NFL referee statistics and analysis. Post your comments if you have suggestions or ideas for the 2009 NFL season (or any lingering questions about the 2007 or 2008 NFL referee statistics).

Super Bowl Penalty and Referee Commentary

2009-02-02T06:29:00.003-05:00

I'll try to compile some of the media commentary on referee Terry McAulay and Super Bowl XLIII between the Cardinals and the Steelers.

First, some of my own thoughts:

Looking at the quality of the calls made (not the statistics):

On the James Harrison interception return for a TD, should the referees have called an illegal block in the back? (Another question is why the players on the sideline stand so close to the field when the action is coming down the sideline? One of the Cardinals players #21 Antrel Rolle was standing close to the sideline and got in the way of Larry Fitzgerald, who was trying to chase down James Harrison but had to slow down when he ran into Antrel Rolle and got there barely too late to stop the TD.)
On the Santonio Holmes TD near the end of the game, Santonio Holmes used the ball as a prop while celebrating the TD. I hate the rule that there's a 15-yard penalty for using the ball as a prop, but the rule is there and shouldn't the referees have called it? If they did, it would have been easier for the Cardinals to try to score in the final seconds.

Other commentary:

Amazing game overshadows all the distractions by Jason Whitlock: the game overcame the officiating, which was "the worst-officiated, sloppiest Super Bowl in league history." Some penalties were obvious while "Some of the other penalties were highly suspicious and lacked common sense. Pittsburgh went up 20-7 in the third quarter thanks to a 16-play, 79-yard, field-goal drive that was significantly helped by a face-mask penalty, a roughing-the-passer flag and an unnecessary-roughness call."
Kurt Warner Was The Real Super Bowl MVP; James Harrison Should Have Been Ejected by Ryan Michael: "My issue with Harrison is what he did during the 4th quarter. Punching another player when he was down then pushing him to the ground. The referees called a deserved penalty but where was his ejection? Looking at that replay you certainly couldn't find any justification for his actions, could you? Had this incident happened with a less popular player in a less popular game, that would be all we would see of him. But because it's the Defensive Player of The Year in the biggest game of the year he gets a free pass? Either the referees were stupid or afraid to be part of the controversy that could have arisen by telling James Harrison to beat it."

Super Bowl XLIII: Steelers 27-23 Cardinals

2009-02-01T22:32:00.002-05:00

Some initial thoughts on the penalty statistics (without looking yet at the quality of the calls):

The final accepted penalties were 11-106 against the Cardinals and 7-56 against the Steelers (including the meaningless personal foul against the Steelers at the end of the game that tended to even off the figures more than it really was while the game was competitive).

Terry McAulay's games in the regular season were especially good for teams that had less penalties and penalty yards called against them. That held up in the Super Bowl. This goes against the grain of what the trend was for the Cardinals and the Steelers in the regular season because those teams did better when they committed more of the penalties, strangely enough.

The Cardinals did better in lower-scoring games than higher-scoring games. This game was in the mid-range, though, so can't say much there.

The Cardinals did better when there were lots of total penalties called, going 5-1 when there were 14 or more total penalties called. This went against the trend because there were 18 total penalties called.

Let's compare the penalty totals to all the regular season games:

The Cardinals had 61.1% of the penalties. Home teams won 51.7% of games with that high of a percent or more of the penalties. Visiting teams won 38.1% of those games.
The Cardinals had 65.4% of the penalty yards accepted. Home teams won 51.5% of games with that high or more of the penalty yards. Visiting teams won 40.8% of those games.

Looking at the quality of the calls made (not the statistics):

On the James Harrison interception return for a TD, should the referees have called an illegal block in the back? (Another question is why the players on the sideline stand so close to the field when the action is coming down the sideline? One of the Cardinals players #21 Antrel Rolle was standing close to the sideline and got in the way of Larry Fitzgerald, who was trying to chase down James Harrison but had to slow down when he ran into Antrel Rolle and got there barely too late to stop the TD.)
On the Santonio Holmes TD near the end of the game, Santonio Holmes used the ball as a prop while celebrating the TD. I hate the rule that there's a 15-yard penalty for using the ball as a prop, but the rule is there and shouldn't the referees have called it? If they did, it would have been easier for the Cardinals to try to score in the final seconds.

Super Bowl XLIII: Cardinals and Steelers, Actual Game Penalty Statistics

2009-02-01T21:12:00.003-05:00

The scoreboard early in the fourth quarter shows the Steelers are heavy favorites to win the game. They have a 20-7 lead early in the fourth quarter.

Let's take a quick look at the penalty statistics. The Cardinals have 9-91 (9 penalties for 91 yards) and the Steelers have 2-15 (2 penalties for 15 yards). This is just as of the early part of the fourth quarter, the game is still going on.

You might think the huge disparity in calls against the Cardinals would work against them in the regular season. Not true -- the Cardinals did especially well in games where there were more penalties called against the Cardinals as opposed to the other team. For example, winning 26-20 at Seattle in week 11 when the Cardinals had 8 penalties and the Seahawks had 1 penalty. The correlation statistics for the Cardinals are -0.428 correlation of percent penalties to scoring margin and -0.494 correlation of percent penalties to won/loss result.

Maybe the answer is that the regular season has too small of a sample size.

This only looks at the raw statistics, not a specific criticism of the quality of the calls being made. Post your comments about specific calls!

The Steelers had a slightly negative correlation in the regular season also, -0.201 correlation of % penalties to scoring margin and -0.113 % penalties to won/loss result.

For all teams, the correlation was minimal: 0.130 to scoring margin and 0.074 to won/loss result.

Super Bowl XLIII (Cardinals-Steelers): Actual Penalties and Actual Total Points

2009-02-01T14:26:00.003-05:00

Let's take a look at how well the Cardinals and Steelers did in the regular season when compared with certain penalty statistics in their games.

The Cardinals did better when they committed more penalties. This seems strange, but the numbers show a correlation. For all teams, there is a -0.033 correlation between the scoring margin to the number of penalties committed, but the Cardinals had a 0.359 correlation. For all teams, there is a -0.063 correlation between the won/loss result and penalties committed, but the Cardinals had a 0.426 correlation. Strange. The Steelers had a -0.061 correlation to scoring margin and 0.137 correlation to won/loss result. This could be how the Cardinals did better in games where the referees called more penalties.

The Cardinals did better in games where there were more penalties. The Cardinals show a correlation of doing better in games where the referees called more penalties (0.117 to scoring margin and 0.248 to won/loss result) while the Steelers had mixed results (-0.151 to scoring margin and 0.057 to won/loss result). The league-wide total was no correlation because in each game, half the teams win and half lose.

The Cardinals did better in lower-scoring games. The Cardinals did better when the actual total points in the game was lower: -0.470 correlation of actual total points to scoring margin and -0.450 correlation of actual total points to won/loss result. The Steelers had mixed results (0.228 to margin and -0.032 to won/loss result). Maybe the key is whether the Cardinals defense can keep the game low-scoring? (The Cardinals went 7-0 when their opponents scored 21 or less, 1-2 when their opponents scored 24 points, and 0-6 when their opponents scored 27 or more.)

If the regular season trends hold up, Cardinals fans should be happy if there are many penalties, if there are penalties against the Cardinals, and the game is low-scoring. Steelers fans should not care much because those details had little correlation with the Steelers during the regular season.

Super Bowl XLIII (Arizona Cardinals-Pittsburgh Steelers 2009): Regular Season Performance With Referees

2009-02-01T14:12:00.003-05:00

What if we looked for trends by the Cardinals and the Steelers during the regular season as it matched up with the referees in each of their games?

I've compared the results of each of the games (both the won-loss result and the margin of victory result) and compared them with the qualities of the referee for that game -- is it a referee who called many penalties during the regular season? Is it a referee who had high-scoring games?

Let's take a look at some trends and how they match up with Terry McAulay, the head referee for Super Bowl XLIII. (Terry has a mixed crew for the Super Bowl, so it does not match up exactly with his regular season statistics, but we'll use it anyway.)

Total accepted penalties and total penalty yards: Pittsburgh did well in games where the referee had more total penalties per game (0.351 correlation to scoring margin and 0.150 correlation to the result). It made little difference to the Cardinals. There is a similar result for total penalty yards (Pittsburgh had 0.353 correlation to scoring margin and 0.167 correlation to the result). Terry McAulay was between 7th and 9th in these categories out of 17 referees so this does not seem to be much of a factor in Terry's games. No advantage.

Both teams did better with referees with higher yards per penalty. No advantage.

Total points scored: The high-powered offense of the Cardinals did better in games where the referee had lower-scoring total points per game. The high-powered defense of the Steelers did better when the referee was one who generally had high-scoring games throughout the season. This seems a bit strange, but that's what the statistics say. The Cardinals had a negative correlation to the total points in the referees' games (-0.386 to margin; -0.500 to result) while the Steelers had a positive correlation (0.177 to margin; 0.154 to result). Terry McAulay had lower-scoring total points per game, ranking 12th out of 17 crews. This factor tends to favor the Cardinals and work against the Steelers. Advantage: Cardinals.

Home team win-rate: the Cardinals did well in games with referees with a low win-rate for home teams (-0.500 to margin; -0.648 to result). The Steelers did well in games with referees with a high win-rate for home teams (0.131 to margin; 0.281 to result). Terry McAulay was tied for the 10th-11th best win-rate for the home team. Out of 17 crews, he was a little lower than average. This factor slightly favors the Cardinals and slightly works against the Steelers. Advantage: Cardinals

Of course, let's not go overboard -- the game will probably be decided by the players, not unexplained correlations to the tendencies during the regular season of the referees. Right?

Terry McAulay and Super Bowl XLIII (Cardinals-Steelers, February 2009): Part Three

2009-01-31T09:45:00.000-05:00

Let's take a look more at Terry McAulay, the referee for Super Bowl XLIII between the Arizona Cardinals and the Pittsburgh Steelers on February 1, 2009.

We know that he has a mixed crew for the Super Bowl, not his usual regular season crew with him, but let's focus on his regular season statistics even though that won't be his complete crew in the Super Bowl.

Teams with less penalty yards won most of the games. In the regular season, the team with less penalty yards accepted against it did extremely well.

Let's start with the raw numbers:

Home teams had less penalty yards in 6 games and went 6-0 (76-43-1 for all refs).
Visiting teams had less penalty yards in 9 games and went 5-4 (64-65 for all refs).
Overall, the team with less penalty yards went 11-4 or 73.3%. (139-108-1 or 56.3% for all refs). I excluded the 5 games where the home and visiting teams had the same amount of penalty yards.

Let's look at correlations:

The correlation to which team won was 0.684 (most for the 17 refs; it was only 0.098 for all refs)
The correlation to the scoring margin was 0.408 (2nd most for the 17 refs; it was only 0.052 for all refs).

Teams with less number of penalties accepted won most of the games. In the regular season, the team with the less number of accepted penalties (ignoring the number of penalty yards) did very well.

Again, let's start with raw numbers:

Home team with less penalties: 6-0 (100%). For all refs, 70-41-1 (62.9%)
Visiting team with less penalties: 5-4 (55.6%). For all refs, 54-60 (47.4%)
Overall the team with less penalties went 11-4 (73.3%). For all refs, 114-101-1 (50.7%)

Let's look at correlations:

The correlation to which team won was 0.614 (most for the 17 refs). It was 0.136 for all refs.
The correlation to the scoring margin was 0.362 (3rd most for the 17 refs). It was only 0.080 for all refs.

For these statistics, Terry McAulay seems overall to have the closest match between penalties called and the odds your team will lose. Roughly speaking, the referees following behind Terry McAulay are Tony Corrente and Gene Steratore. On the other side, the complete opposite of Terry McAulay was Jeff Triplette.

It's difficult to categorize, but the referee with roughly the least correlation between penalties (yards and number) and the game result (scoring margin and raw result) was Walt Coleman. Funny, Walt Coleman had the least number of penalties during the regular season.

Terry McAulay and Super Bowl XLIII (Cardinals-Steelers, February 2009): Part Two

2009-01-28T20:35:00.002-05:00

Terry McAulay will be the head referee in Super Bowl XLIII between the Arizona Cardinals and the Pittsburgh Steelers on February 1, 2009.

For this second post, let’s look at whether a good offense or a good defense is more important for Terry’s regular season games.

If you look at all 2008 regular season games for all referees, the home team’s offense is the most important followed by the visiting and home team’s defenses. The least important factor is the visiting team’s offense. This does not help us with the Super Bowl because it is a neutral field game -- unless you look at the Super Bowl as if both teams are visitors...

Anyway, let’s take a look at the combined offenses and defenses and see whether a stronger offense or stronger defense was better for the home team. We focus on the perspective of the home team rather than on the stronger team regardless of whether home or visiting to reflect how there is a home team advantage.

Looking at all the games for all referees, there is a similar correlation to the margin of victory for a better offense and a better defense. If we focus on which team won (regardless of the margin of victory), it is more important to have a stronger defense than a stronger offense (0.365 versus 0.288 correlation).

Now let’s focus on Terry McAulay’s regular season games: just like with the analysis of all referees, it is equally good to have a better offense and a better defense when you compare correlations to the margin of victory. But if we focus on which team won (regardless of the margin of victory), it is even more important for Terry than for most referees to have a stronger defense than to have a stronger offense (0.425 versus 0.233 correlation). This favors the Steelers in the Super Bowl.

Take a look at games where one team had a stronger defense but a weaker offense (similar to the Pittsburgh Steelers in the Super Bowl), those teams went 4-3 in Terry’s regular season games. If you exclude the games where one team’s advantage was less than one point per game, the teams went 3-1.

For the 3-1 record, the games where the better defense won over the better offense were: (three wins) Buccaneers 30-21 Packers, Steelers 38-17 Texans, Bills 30-23 Broncos and (one loss) Raiders 3-34 Saints.

This could be good news for the Steelers, but watch out for the really small sample size!

Strong Defense Slightly Better Than Strong Offenses In 2008

2009-01-25T15:49:00.002-05:00

Teams with much better defenses did better than teams with much better offenses in the 2008 NFL regular season, but only by a little more than you'd expect from the usual home field advantage so it might not be much of an advantage.

In Super Bowl XLIII, the Pittsburgh Steelers have a much better defense but the Arizona Cardinals have a much better offense. How did this combination of factors play out in the 2008 regular season?

Let's use the number of points scored and given up as a rough measure of how good a team's offense and defense is. It is not certainly not perfect for a variety of reasons (no adjustment of strength of schedule or garbage time scoring), but it is a simple objective measure for our analysis.

Next, let's look at agmes where one team had a stronger offense (better than one point per game) and the other team had a stronger defense (better than one point per game).

When home teams had a stronger offense but weaker defense, they went 22-18, just slightly worse than the average for home teams. When visiting teams had a stronger offense but weaker defense, they went 14-22, slightly worse than the average for visiting teams. This suggests the team with the better defense does slightly better, so a slight advantage to the Steelers.

If we look at teams that had a much stronger offense (better than 5 points per game advantage) but a weaker defense (worse than 5 points per game advantage), we see that this only happened for visiting teams with strong offenses and weaker defenses. It happened 5 times and the visiting team went 2-3, slightly worse than the average for visiting teams, but too small of a sample size to make much of a conclusion.

This analysis doesn't take into account how the Steelers have an advantage with its defense (13.5 points per game) that is much bigger than the Cardinals have a better offense (5.3 points per game).

Terry McAulay and Super Bowl XLIII (Cardinals-Steelers, February 2009): Part One

2009-01-25T10:30:00.003-05:00

Terry McAulay will be the head referee in Super Bowl XLIII between the Arizona Cardinals and the Pittsburgh Steelers on February 1, 2009.

For the first post, let's take a look at some basics for Terry McAulay:

Some general statistics: total penalties 11.2 (7th of 17 referees), total yards 89 (tied for 8th), average penalty yards per penalty 7.9 (7th), percent penalties against visiting team 49% (10th), total points 41.9 (12th), visiting team points 18.9 (14th), home team points 23 (tied for 10th).

By the way, he has one of the highest home-team win rates out of the 17 referees. In 2008, it was 67%, tied for second. In 2007, it was 75%, which was at or near the highest in 2007. Wonder which team in the Super Bowl would have more fan support to make it seem a bit like a home game.

Terry's games this season include the AFC second-round (the NFL calls it the divisional playoff games) where the Baltimore Ravens beat the Tennessee Titans with a 43-yard field goal on a drive where they snapped the ball after the play clock expired but the referee crew did not call a delay-of-game-penalty. Titans coach Jeff Fisher has called the mistake unacceptable.

The Steelers have the advantage of being more familiar with Terry's games. In week 1, the Steelers hosted the Texans and won 38-17 in a game that Terry McAulay covered.

In Terry McAulay's regular season games, the margin of victory was one of the closest to correlate to what was expected if you look at the won-loss record of the teams or if you look at the net points scored of the teams. Terry was 3rd of 17 referees at 0.420 correlation to the home team's margin of victory excluding the game covered. He was 4th at 0.571 correlation to the home team's won-loss advantage.

The correlation to which team won the game (ignoring the margin of victory) put Terry in the middle of the pack, 9th based on home team's margin of victory excluding the game covered and 11th based on home team's won-loss advantage.

Walt Anderson and the Eagles-Cardinals NFL Championship Game: Final Part

2009-01-19T09:28:00.004-05:00

Let's take a wrap-up look at Walt Anderson and the Eagles-Cardinals game.

Interesting calls: (post a comment for calls I didn't catch during the game).

3:06 left in the second quarter, short kickoff by the Cardinals possibly hits the fingertips of Eagles blocker Victor Abiamiri (who was at the time inbounds), hits the ground inbounds, then bounces up and possibly hits the arm of Victor Abiamiri (who by that time was standing out of bounds). Some of the first replays suggest it missed Abiamiri's fingertips, hit the ground, and on the upswing hit the Abiamiri's arm. The announces stopped analyzing the play once it was not reviewable, but the proper analysis seems to be that if it was inbounds until it hit an out-of-bounds Abiamiri, the kick should have been flagged as a kickoff out of bounds and the Eagles should have gotten the ball on their 40 yard line (not the spot it went out of bounds, which was only the 27 yard line and cost the Eagles 13 yards). The Eagles eventually gained 9 yards then punted and the Cardinals brought the ball back just enough to kick a 49-yard field goal.
1:51 left in the fourth quarter. Eagles QB Donavan McNabb throws a pass on 4th and 10 from the Cardinals 47 and Eagles WR Kevin Curtis is unable to catch it, but complains that just before the ball arrived, a Cardinals defender clipped his leg. The replays suggest that the Cardinals defender perhaps accidentally fell down as the ball was about to arrive and while falling, hit Curtis's leg to some degree. It did not seem intentional, which might have influenced the referee's call. Also, it is not clear how much hitting the leg affected the play -- can't really tell that clearly from the replay.

The penalty statistics in the game (which was done by a combination-crew) compared with the regular season statistics for Walt Anderson's full crew and all regular season games:

% penalties against home team: 30% (only one of Walt's 14 regular season games had less -- strangely, a game where the home team lost despite the favorable penalty numbers). For all regular season games, 32 of 256 games (13%) had 30% or less and home teams won 66%.

% penalty yards against home team: 19% (less than all of Walt's 14 regular season games). For all regular season games, 10 of 256 games (4%) had 19% or less and home teams won 70%.

Bill Carollo: Baltimore Ravens - Pittsburgh Steelers AFC Championship Game

2009-01-18T14:51:00.003-05:00

Several bloggers and newspapers report that Bill Carollo is scheduled to be the lead referee for the AFC Championship Game between the Ravens and the Steelers. It will be a mixture of crews, so analysis of Bill in the regular season will not apply as much as it would if it were his regular crew. Still, let's take a look at Bill's 2008 NFL regular season.

Raw statistics: 9.8 penalties per game (16th of 17 refs), 77 penalty yards (14th), 7.9 yards per penalty (8th), 53% penalties against visiting team (3rd), 55% penalty yards against visitors (2nd), 39.3 total points scored (17th and last), 18.9 points by visiting teams (13th), 20.3 points by home teams (15th), home teams won 50% (tied for 12th and 13th).

So Bill had the lowest scoring games in the regular season and called some of the least number of penalties per game.

Let's take a quick look at how well favorites do with Bill. If you define favorites as the team with the better net points per game, Bill comes out in the middle of the pack with a correlation of 0.430 (9th of 17) to the winning team (regardless of the final score) and 0.562 (5th) to the scoring margin at the end of the game. The Ravens had a slightly better scoring margin in the regular season than the Steelers.

If you define favorites as the team with the better won-loss record in the regular season, Bill comes out with a slight correlation of 0.114 (11th) to the winning team and some correlation of 0.236 (7th) to the scoring margin at the end of the game. The Steelers had a slightly better won-loss record in the regular season than the Ravens.

Walt Anderson and the Eagles-Cardinals NFC Championship Game: Part Two

2009-01-18T10:45:00.005-05:00

Several bloggers think that Walt Anderson (referee #66) will be the ref for the Eagles-Cardinals NFC Championship Game.

Let's take a look at some more statistics for his 2008 regular season.

The Eagles have a slightly better winning percentage than the Cardinals did in the regular season. Better record teams did better in Walt's games with a 0.399 correlation (10th of 17 refs) to which team won and a 0.220 correlation (14th of 17) to the scoring margin.

The Eagles have a better net scoring margin than the Cardinals, better by 3.9 points per game. Walt had little correlation between net scoring margin and the results of his games, though: 0.022 correlation (12th of 17) to which team won and -0.141 correlation (16th out of 17) to the scoring margin.

In another posting, I'll go into how there is an interesting trend through both halves of the 2008 NFL season: the most important factor to which team wins and the scoring margin is the home team's offense. Next important are pretty equal -- the visiting team's offense and the home team's defense. The least important factor is the visiting team's offense. Interesting details!
The Eagles had Walt in the 2008 season and lost 36-7 at Baltimore in week 12. The Cardinals did not have Walt.

Let's take a look at specific games for teams with a better winning percentage.

When the home team had a better record (other than the game Walt was doing), the home teams went 5-1. When the visiting team had a better record, the home teams went 4-4.

Alberto Riveron Best For Favorites And Walt Coleman Best For Underdogs

2009-01-17T14:50:00.001-05:00

Which referees are better for the favorites than others?

To look into this, I looked at how well the stronger team did in a referee’s 2008 regular season games did. First, I will focus on the correlation between how much stronger the favorite was and whether the team won (regardless of the scoring margin, so this is focused on won-loss, not margin of victory or beating the spread). A strong predictor of which team is stronger is comparing the net scoring margin for the teams.

By crunching the number for the entire season, we come up with a ranking of the correlation between how much stronger the favorite is and the winning percentage for the favorite. That shows us which referees are better for favorites. Let me know your criticisms or comments on this approach!

The best referees for favorites are Alberto Riveron, Scott Green, Jeff Triplette, and Carl Cheffers.

If your team is an underdog when you look at the net scoring margin, then you want (in order of preference): Walt Coleman, Gene Steratore, John Parry, and Jerome Boger.

I am ranking them by how well the expected scoring margin correlated to which team won. Alberto Riveron was highest with 0.781 and Walt Coleman was lowest with 0.199. For games with all referees, the correlation was 0.512.

There is a big difference between Alberto Riveron and Walt Coleman. The team with the better scoring margin went 14-2 with Alberto Riveron, but only 9-6 with Walt Coleman and 7-8 with Gene Steratore.

For those who expect Walt Anderson to referee the Eagles-Cardinals game, he was 13th out of 17 with a correlation of only 0.395.

Walt Anderson and the Philadelphia Eagles-Arizona Cardinals NFC Championship: Part One

2009-01-14T22:41:00.004-05:00

A few message boards and blogs are suggesting that Walt Anderson might be the referee for the Eagles-Cardinals NFC championship game.

If that's the case, let's look at Walt Anderson's statistics for the full 2008 NFL season. It's possible the NFL will assign a mixed crew for him, so maybe these statistics won't apply completely, but it's what we have so let's take a look at them even if we have to hedge a bit because his crew might be a little different.

In this post, we look at some basic statistics. We'll look at more specific statistics in another blog posting soon.

Rankings are out of 17 referee crews

Penalties per game: 12.6 (3rd). 12.7 in 2007

Penalty yards: 96 (6th). 97 in 2007

Yards per penalty: 7.7 (13th). 7.6 in 2007

Percent penalties on visiting team: 52% (5th). 50% in 2007

Number of penalties on visiting team more than home team: 0.6 (4th). 0 in 2007

Total points: 41.2 (13th) 41.7 in 2007

Visitor points: 17.9 (17th and last). 20.3 in 2007

Home points: 23.4 (9th). 21.3 in 2007

Home win rate: 64% (4th), 60% (9th) in 2007

So visiting teams scored very little in Walt's games in 2008. Generally he had lower-scoring games. It wasn't due to the strength of the teams, either. If you look at the overall scoring and defenses of the teams in Walt's 2008 games, they would have worked out to be equal for visiting teams and home teams.

More statistics and analysis to come later...

Referee Bill Leavy and the Chargers-Steelers Playoff Game

2009-01-11T18:40:00.002-05:00

Now that the game is underway, it looks like Bill Leavy is the referee for the NFL playoff game between the San Diego Chargers and the Pittsburgh Steelers.

Basic Statistics
First, some basic statistics. Rankings are out of 17 NFL referee crews.

Total penalties accepted: 10.7 (11th), 12.1 in 2007
Total yards: 83 (11th), 94 in 2007
Yards per penalty: 7.8 (10th), 7.7 in 2007
% penalties on visitors: 51% (7th), 56% in 2007
% penalty yards on visitors: 49% (7th), 54% in 2007
Total points scored: 50.2 (2nd), 41.5 in 2007
Visitors points: 24.2 (1st), 21.0 in 2007
Home points: 26.0 (3rd), 20.5 in 2007
% home win rate: 60% (tied for 7th through 10th), 45% in 2007

So what's striking is that his game had lots of points scored (2nd highest for total points, highest for visiting teams, 3rd highest for home teams). Yet home teams scored more than visiting teams overall and won 60% of the games, which is roughly middle of the pack.

San Diego has seen Bill this season in a week 6 win over the New England Patriots 30-10. Pittsburgh has not seen Bill this season.

Analyzing Won-Loss Records of Bill's Games
Steelers have 4 more regular season wins than the Chargers. When the home team had more wins (excluding the game Bill covered) in the regular season, the home team went 5-1. Specifically, +11 (win), +6 (win), +6 (win), +3.5 (win), +1 (loss), +1 (win).

By the way, when the home team was equal, the home team went 1-0, and when the home team had a worse record, the home team went 3-5.

Another way to look at it is that the team that had the better record went 10-4 in Bill's games in the regular season.

Analyzing Net Points Records of Bill's Games
The Steelers are +1.0 in net points over the Chargers.
Home teams with more than 1.0 in net points advantage went 5-0.
Home teams with 0.7 net points advantage went 1-1. (Vikings 34-14 Bears; Jets 17-24 Dolphins)
Home teams with between +0.5 and -0.5 advantage went 2-0
Home teams with -1.0 or worse went 1-5.
There is more of a correlation between the net points and the final scoring margin in Bill's games than the won-loss records.

Terry McAulay and the Ravens-Titans Playoff Game

2009-01-10T18:31:00.003-05:00

Terry McAulay is the referee for the Baltimore Ravens-Tennessee Titans playoff game. Let's take a quick look at our statistics for him in the 2008 NFL regular season.

He has one of the highest home-team win rates out of the 17 referees. In 2008, it was 67%, tied for second. In 2007, it was 75%, which was at or near the highest in 2007. This is good news for the Titans if you believe this is a trend.

If you look at the schedule, though, 9 of the 15 games had home teams with a better record than the visiting teams, so maybe it was just a reflection of the schedule.

In the regular season, the Titans had 2 more wins than the Ravens. When the home team had more wins, they went 7-2 in Terry's games.

If we look at the net margin of victory, the teams are equal. In the regular season, when the visiting team had only a slightly better margin of victory, the visiting team won (Giants at Eagles, week 10). Once they were pretty much equal and the home team won (Packers at Bucs, week 4).

Some general statistics: total penalties 11.2 (7th of 17 referees), total yards 89 (tied for 8th), average penalty yards per penalty 7.9 (7th), percent penalties against visiting team 49% (10th), total points 41.9 (12th), visiting team points 18.9 (14th), home team points 23 (tied for 10th).

2008 NFL Team Schedules by Referee Home-Win Rate

2009-01-10T12:21:00.003-05:00

What if we assumed just for the sake of argument that every referee has a tendency to favor home or visiting teams by the same degree throughout the year. This is not what we really think, but it can lead us to some statistics that we can discuss and debate.

Let's take the home team win-rate for each referee and see which teams had the easiest and hardest NFL referee schedule in 2008.

Using each referee's actual home-team win rate in 2008 and combining that with each NFL team's referee schedule, here are the statistics. Post your thoughts and comments!

Team, followed by expected wins based on 2008 NFL referee schedule:
Carolina Panthers 8.75
Miami Dolphins 8.47
New Orleans Saints 8.45
Baltimore Ravens 8.41
New England Patriots 8.37
Atlanta Falcons 8.35
Minnesota Vikings 8.30
Pittsburgh Steelers 8.24
Philadelphia Eagles 8.23
New York Jets 8.21
Indianapolis Colts 8.20
Tennessee Titans 8.17
Tampa Bay Buccaneers 8.11
Washington Redskins 8.11
Jacksonville Jaguars 8.10
San Francisco 49ers 8.07
Denver Broncos 8.03
Cincinnati Bengals 8.01
Detroit Lions 7.93
Oakland Raiders 7.92
New York Giants 7.91
Houston Texans 7.89
Arizona Cardinals 7.84
Dallas Cowboys 7.76
St. Louis Rams 7.76
San Diego Chargers 7.68
Cleveland Browns 7.65
Seattle Seahawks 7.58
Chicago Bears 7.53
Green Bay Packers 7.35
Buffalo Bills 7.32
Kansas City Chiefs 7.28

If you believe this chart, then maybe the Carolina Panthers and Miami Dolphins are not as strong as their record would indicate because they had favorable referee schedules. On the other hand, the San Diego Chargers, Arizona Cardinals, and NY Giants made the playoffs despite having unfavorable NFL referee schedules. Maybe they are stronger than their records would suggest?

Any other insights if we play along with this chart? That the Chicago Bears (barely missed a wild card spot) might have had a better season with a more favorable referee schedule? That the New England Patriots (barely missed a wild card spot) can't really complain because they had a very favorable referee schedule?

Referee Jeff Triplette and the SD Chargers - Pittsburgh Steelers Playoff Game

2009-01-10T10:02:00.005-05:00

I don't know for certain who will be the referee in the Chargers-Steelers playoff game but a few people think it will be Jeff Triplette. Let's take a look at the statistics for Jeff Triplette in the 2008 regular season.

UPDATE: Looks like Bill Leavy is the ref, not Jeff Triplette, so let me try to do a new blog post with statistics on Bill Leavy instead. Look for a separate post on Bill Leavy.

Recent history:
2008, wk 17: Cleveland Browns 0-31 Pittsburgh Steelers
2008, wk 7: San Diego Chargers 14-23 Buffalo Bills
2007, wk 15: KC Chiefs 9-20 San Diego Chargers
2007, wk 3: Cincinnati Bengals 28-20 Pittsburgh Steelers

So, the Steelers have more recent experience with Jeff Triplette's crew and this year, Steelers won and Chargers lost with him. But in 2007, it was the reverse -- Chargers won and the Steelers lost.

Home teams went 9-6 in Jeff's games in 2008. (They went 10-5 in 2007.)

Let's take a look at how home teams did in games using the won-loss record (excluding the game that Jeff Triplette did) as a yardstick:

When the home team had more wins, they went 5-1. When equal, 1-1. When less, 3-4. In the regular season, the home team Steelers had 4 more wins than the Chargers.
Correlation between won-loss record and margin of victory was 0.66

Let's use the net points scored as the yardstick rather than won-loss records:

When the home team had a better net points total, they went 6-1, when roughly equal, 1-0, when less, 2-4. In the regular season, the Steelers had 1.0 better net points total per game than the Chargers.
Correlation between net points total and margin of victory was 0.78

Total points scored: using the particular teams in Jeff's regular season games, you'd expect 43.9 points per game and the actual results were close: 43.6 total points per game in Jeff's games. The actual results were an average of 20.9 points by visiting teams and 23.0 points by home teams this season. (In 2007, it was 18.2 for visitors and 25.3 for home teams.)

Regular Season Statistics:
Very large number of total accepted penalties per game. Out of 17 referees, he had 12.5 per game (2nd). Pretty large total penalty yards accepted per game at 99 (4th). Middle of the pack for yards per penalty (8.0, 9th) and percent of penalties called against the visiting team (49%, 9th). Also pretty average for total points scored per game (43.9, 9th). Visiting team points per game was 21.0 (8th) and home team points per game was 22.9 (tied for 10th).

The home win rate was 57%, which was middle of the pack, tied for 7th through 10th. (This season, home teams won 57.2% of the games.)

The 2007 Regular Season:
For comparison purposes, here is what we wrote about Jeff Triplette and the 2007 regular season: Tied for 5th out of 17 for best ref for the home team's winning rate (67%). Near the bottom in penalties per game (14th) and yards per penalty (15th) so of course near the bottom in penalty yards per game (15th). 4th-most for percent of penalties called against the visiting team (55%). Middle of the pack (9th) in total points scored per game and near the top (4th) in home team points scored per game. Near the bottom (16th) in amount of penalty yards called against the home team at just 36.8 per game. Tied at the top in the percent of his games in which the visiting team had more penalties than the home team (70%). Overall, home teams did pretty well in Jeff's games during the regular season with not so many penalties called per game -- especially few called against the home team.

Please post a comment if you find this helpful or have questions. Remember, I'm not certain whether the referee for the SD-Pittsburgh game really will be Jeff Triplette. UPDATE: looks like Bill Leavy so I'll try to put a new blog post on him.

Ron Winter in the Colts-Chargers Wild Card Game

2009-01-04T09:56:00.006-05:00

There was a great deal of controversy over Ron Winter's referee crew in the wild card game between the San Diego Chargers and the Indianapolis Colts.

I will try to crunch the numbers for his crew for the 2008 NFL season to see if I can spot any trends from the raw statistics that I've been tracking.

The controversy seems to be up for debate, as opposed to other games this season where people unanimously believed the referees made mistakes.

Some questions (with critics and defenders of the referees for each point) include:

10:04 left in OT, defensive holding called on Colts's CB Tim Jennings on what would otherwise have left SD with a 4th-and-8 on the Colts's 40 yard line. Some think it should not have been a penalty while others think it was a penalty and should have been defensive pass interference.
12:51 left in OT, defensive holding on the Colts's DT Eric Foster.
Non-calls against SD for possible offensive holding or illegal hands to the face while stopping DE Dwight Freeney.
Non-call in OT against Chargers's center Nick Hardwick for possible holding.

The accepted penalties ended up at 9 penalties for 74 yards against Indianapolis and 3 penalties for 40 yards against San Diego.

That does not include 2 penalties called against the Colts that were declined. (If you include those, then the called penalties were 11 against the Colts and 3 against the Chargers.) I'll look into how this compares with regular season games this season...

Ron Winter and the 2008 NFL regular season referee statistics:

13.6 accepted penalties per game, 1st out of 17 crews (2nd was 12.7). His crew also had the most in 2007.
114 accepted penalty yards per game, most (2nd was 107). He was 2nd in 2007.
8.4 penalty yards per penalty, 3rd most. He was 9th in 2007.
49% of penalties were against the visiting teams (12th out of 17)
45.3 points per game (7th of 17)
24.8 points by the home team per game (5th of 17)
63% of the time, the home team won (6th of 17). He was tied for 15th in 2007 (40%). The league average was 56.8% this year (2008).

Was the game unusual for having 9 penalties for 74 yards for the visiting Colts and 3 penalties for 40 yards for the home team (Chargers)?

Is it unusual for there to be a 6 penalty disparity in favor of the home team? In the 2008 season, out of 256 games, one was +9 for the home team, 2 were +8 for the home team, 3 were +7 for the home team, and 6 were +6 for the home team. So only 12 of 256 games were +6 or more for the home team. (Home teams won 50%)
Is it unusual to have only 25% of the penalties against the home team? There were 12 games where the home team had less than 25% of the penalties and 5 games where the home team had 25% of the penalties -- so in 17 out of 256 games the home team had 25% or less of the penalties. Home teams won 76% of those games. Putting aside games where the disparity was 4-0, 4-1, 3-1, or 5-1, the list is:

Scott Green, StL-NE, 9-0 penalties
William Carollo, Ariz-Sea, 8-1
Tony Corrente, Ind-Hou, 6-1
Terry McAulay, TB-Atl, 11-3
Gene Steratore, NO-Atl, 7-2
Terry McAulay, NYG-Minn, 7-2
Bill Leavy, Det-SF, 9-3
Peter Morelli, NYG-Ariz, 9-3
Walt Anderson, Car-SD, 6-2
[Ron Winter, Ind-SD, 9-3]

Is it unusual that 35.1% of the penalty yards were called against the home team? Not really. Out of 256 games, the home team had less than 35% of the penalty yards in 49 games. (Home teams won 59%)
There were 29 games in the regular season where the visiting team was penalized by 34 or more yards than the home team. (Home teams won 54%)
Home teams had 3 or less accepted penalties in 57 games (home teams won 69%)
Home teams had 40 penalty yards or less in 125 games (home teams won 60%)
Visiting teams had 9 or more accepted penalties in 37 games (home teams won 57%)
Visiting teams had 74 or more penalty yards in 26 games (home teams won 62%)

How did home teams do for Ron Winter's games considering the particular won-loss records of the teams (excluding the game that Ron Winter did)? Let's use the won-loss record as a yardstick for whether we'd expect a team to win.

The Colts-Chargers game had the home team with 4 less wins than the visiting team. Here is Ron Winter's distribution, listing how many more victories the home team had other than the game Ron did and whether the home team won. The Colts-Chargers game had a home team net record of -4: -8L, -7W, -6L, -1.5L, -1L, -1W, 0L, 0W, 2W, 2W, 2.5W, 5L, 5W, 6.5W, 8W, 10W. So it looks like when the home team has less wins, they went 2-5 and when it had more wins, it went 7-1. The biggest upset in favor of a home team was in week 7, when the home team Green Bay beat the visiting Colts 34-14.

Another way to predict how good teams are is to check only the points scored and points allowed, but not their won-loss rate. Using this approach, SD was favored by 0.4 points (their net points was better than the Colts's.)

When the home team has better net points, they went 6-1 with Ron Winter's games this season. When the home team was equal or -1, they went 2-0. When the home team was more than 1.0 points an underdog using this method, they went 2-5.

Requests for More Analysis of a Particular Referee Crew?

2009-01-01T13:18:00.001-05:00

Post a comment about which referee crew you would like more analysis about. There are several referee crews and too many for me to try to analyze all at once. Post a comment with your request of which one you'd like me to focus on. If you include an explanation why, that might help me out, too!

Controversial Referee Calls: A Working List

2008-12-26T10:33:00.000-05:00

Is there a good compilation of the controversial referee calls from the NFL season? Let's start a working list and please post some comments of some of the controversial calls that we should add to the list.

Also, let me know in the comments whether you think we should make a wiki so that people can add their own comments about the referees.

NFL 2008 Season

Week 2: Ed Hochuli, SD Chargers-Denver Broncos. Broncos QB Jay Cutler lost the ball when moving his arm back, which caused a fumble that SD recovered just after referee Ed Hochuli mistakenly blew the play dead for a supposed incomplete pass. In the aftermath, the NFL fined Jerry Jones $25,000.
Week 3: Ron Winter, NO Saints-Denver Broncos. Broncos LB Jamie Winborn was not called for offside on a play. Saints coach Sean Payton complained about that later and the NFL fined him $15,000.
Week 4: Ed Hochuli, Atlanta Falcons-Carolina Panthers. Carolina DE Julius Peppers hit Falcons QB Matt Ryan and Ed Hochuli called a disputed penalty for roughing the passer, negating a fumble.
Week 6: Ed Hochuli, Miami Dolphins-Houston Texans. Generally, Dolphins LB Joey Porter criticized Ed Hochuli and his crew on a call that a potential fumble was an incomplete pass, which Joey Porter thought was an example of how the Texas kept getting calls. The NFL fined him $20,000.
Week 6: Bill Carollo, Jacksonville Jaguars-Denver Broncos. Denver CB Dre Bly questioned calls by Bill Carollo's crew, including an illegal-contact call against Dre Bly and a defensive pass interference call against his teammate Marlon McCree. The NFL fined him $20,000.
Week 7: Walt Anderson, SF 49ers-NY Giants. NYG WR Plaxico Burress and SF CB Nate Clements got together on a pass to Burress. An official on Walt Coleman's crew called it offensive pass interference on Plaxico Burress, but replays suggested it should have been defensive pass interference on Nate Clements. Plaxico Burress later criticized it as one of the worst calls he'd ever seen. The NFL fined him $20,000.
Week 10: Tony Corrente, Arizona Cardinals-SF 49ers. SF RB Frank Gore was tackled before reaching the end zone and at first, referees placed the ball inside the 1-yard line. After reviewing the play, they moved the ball back to the 2-yard line but SF claims that the referees did not tell the SF coaches, who had to go ahead and run a play that was not suited to gaining two yards and failed.
Week 11: Scott Green, SD Chargers-Pittsburgh Steelers. Pitt CB Troy Polamalu picks up a botched lateral and returns it for an apparent TD on the final play of the game. After reviewing a replay, referee Scott Green applies the rules incorrectly and overturns the TD because he thought the play should have been dead when the lateral hit the ground -- a ruling that would only be correct if the lateral in question was an illegal forward pass such as a toss earlier in the play. Gamblers around the country groan.
Week 15: Walt Coleman, Pittsburgh Steelers-Baltimore Ravens. Pitt WR Santonio Holmes caught a ball right at the goal line and the referees ruled on the field that he was stopped just short of scoring a TD. After reviewing replays, they overruled the call and ruled that it was clearly a TD. Many commentators believed the replays were not clear about whether it was a TD -- even though it suggested it probably was a TD, it was not clear enough to justify overruling a call on the field.

NFL Referee Statistics before Week 16 (up to December 15, 2008)

2008-12-21T12:51:00.000-05:00

About time I caught up on some statistics!

For now, just some raw statistics after the first 15 weeks (through the games of Monday, December 15, 2008).

Referee, Penalties accepted per game, Penalty yards accepted per game, Yards per penalty accepted, total points scored, % home win rate.

If you are rooting for the home team and you think some referees are better for the home team than others, then hope you get Alberto Riveron (71%), Scott Green (69%), or Terry McAulay (67%). But not John Parry (38%), Gene Steratore (43%), or William Carollo (43%)! These are raw figures, not adjusted for the strength of schedule.

After 15 weeks, home teams are winning 56.5% of the games. Note, for weeks 9-15, the home win rate was only 49.5% (I wondered last year whether the home field advantage decreases towards the end of the season...)

Anderson, Walt 13.1 101 7.7 38.7 67%
Boger, Jerome 12.8 97 7.6 44.2 62%
Carey, Mike 10.2 91 8.9 42.4 45%
Carollo, William 10.3 78 7.6 40.2 43%
Cheffers, Carl 9.8 81 8.3 46.0 46%
Coleman, Walt 9.4 70 7.5 45.1 57%
Corrente, Tony 13.2 114 8.7 42.6 50%
Green, Scott 10.5 75 7.2 42.2 69%
Hochuli, Ed 12.6 102 8.1 43.1 50%
Leavy, Bill 10.7 84 7.9 50.6 62%
McAulay, Terry 11.5 90 7.9 41.3 69%
Morelli, Peter 10.8 82 7.5 49.1 65%
Parry, John 11.4 86 7.6 43.8 38%
Riveron, Alberto 11.1 88 8.0 47.5 71%
Steratore, Gene 10.8 84 7.8 42.5 43%
Triplette, Jeff 13.0 101 7.8 42.9 62%
Winter, Ron 14.1 116 8.3 45.2 64%

Walt Coleman In The Middle of A Replay Controversy

2008-12-15T21:20:00.002-05:00

Big controversy over Walt Coleman's decision on December 14, 2008 to overturn the ruling on the field by head linesman Paul Weidner -- Santonio Holmes of the Pittsburgh Steelers caught a pass that the officials initially called as down on the one-foot line and not a touchdown. After the review, Walt Coleman overturned the ruling on the field and called it a touchdown, infuriating Baltimore Ravens fans.

Many people are wondering whether there was conclusive evidence that would be enough to overturn the decision on the field. Chris Mottram of the Sporting News thinks it probably was a TD but not enough to overturn the decision on the field. NBC analyst Cris Collingsworth thought it wasn't a TD. Peter King of CNN thought it was most likely a TD but not enough to be indisputable evidence. Gene Wang of the Washington Post thought Walt Coleman got it the evidence was in no way conclusive.

Patrick McManamon of the Ohio Beacon Juornal wrote that there's no way it should have been overturned by replay and even suggests the NFL would be better off without replay.

NFL Referee Statistics: Correlations within the same season

2008-11-15T12:47:00.003-05:00

Let's look for correlations within the same NFL season for NFL referee statistics. Let's line up the referees for their statistics from weeks 1-5 and then line them up for their statistics from weeks 6-10 and see if there are correlations between how they are distributed for weeks 1-5 and weeks 6-10. If there is a strong correlation, then it seems the order they were for their work from weeks 1-5 was a perfect predictor for how they would be ordered for their work in weeks 6-10. This analysis is not looking between statistics of different seasons (we're not checking the 2007 NFL referee statistics for this).

Strong correlations between weeks 1-5 and weeks 6-10 for:
Percent penalties against visiting teams (0.338)
Percent penalty yards against visiting teams (0.343)
Total points scored (0.219)
Total points scored by teh home team (0.253)
Penalties against the home team (0.112)

No correlation for a few categories:
Home team winning rate (0.036)
Total number of accepted penalties (0.009)
Penalties against the visiting team (-0.026)

A negative correlation for a few categories:
Points scored by the visiting team (-0.184)
Total penalty yards (-0.137)
Average yards per penalty (-0.130)

Intriguing or just a bunch of random statistics?

NFL Referee Statistics After Week 10 (through games of 11/10/08)

2008-11-15T12:39:00.001-05:00

Just a quick update this week -- this includes all the games of week 10, through the game on Monday, November 10, 2008.

No narrative explanation (anything you would like to focus on next time?). Just some statistics this time:

Referee, Penalties accepted per game, Penalty yards accepted per game, Yards per penalty accepted, % of accepted penalties against the visiting team, % of accepted penalty yards against the visiting team, total points scored.

Anderson, Walt 13.0 99 7.6 54% 54% 36.5
Boger, Jerome 15.2 113 7.4 43% 41% 44.8
Carey, Mike 10.3 88 8.5 43% 43% 41.1
Carollo, William 11.4 89 7.8 52% 55% 41.4
Cheffers, Carl 10.1 85 8.4 42% 35% 45.8
Coleman, Walt 8.8 69 7.8 63% 65% 44.1
Corrente, Tony 13.7 126 9.2 50% 53% 42.7
Green, Scott 10.8 75 7.0 53% 53% 47.5
Hochuli, Ed 12.7 102 8.1 51% 45% 47.2
Leavy, Bill 10.5 81 7.7 55% 53% 48.1
McAulay, Terry 11.6 97 8.4 47% 43% 48.2
Morelli, Peter 10.8 77 7.1 53% 56% 49.8
Parry, John 12.3 93 7.6 51% 48% 42.6
Riveron, Alberto 11.6 99 8.6 46% 46% 44.1
Steratore, Gene 10.1 79 7.8 58% 58% 40.2
Triplette, Jeff 15.1 117 7.7 46% 41% 42.5
Winter, Ron 14.0 114 8.1 48% 50% 49.1

NFL Referee Statistics: Correlations from Season to Season

2008-11-09T13:21:00.002-05:00

Which statistics for NFL referees seem to hold up from season to season? Let's test this by looking at the correlation across the spread of referees from one season to the next. For example, if the ranking of which referees have the highest accepted penalties per game is the same from one season to the next, we would see a strong correlation from year to year.

This is based on a comparison of the 2007 season to the first 9 weeks of the 2008 season and also a comparison of the 2006 season to the 2007 season.

Total accepted penalties per game has a strong correlation from year to year: 0.503 from 2007 to 2008 so-far and 0.392 from 2006 to 2007. Same for total accepted penalty yards per game with 0.516 for 2007 to 2008 so-far and 0.394 for 2006 to 2007.

So it seems that some referee crews year in and year out consistently call more penalties than other referee crews. Maybe some are sticklers for the rules and others let things slide.

There is also a correlation across the years for the number of accepted penalties called against the visiting team (0.275 this year and 0.123 last year), accepted penalty yards against visiting teams (0.236 this year and 0.332 last year), accepted penalties against home teams (0.298 this year and 0.489 last year), and to some degree accepted penalty yards against home teams (0.088 this year and 0.417 last year).

There is no correlation from year to year for the home team's win rate so far (this year 0.009 and last year -0.172). One point, though, is that there is such a small sample size. After the first eight weeks, Peter Morelli went from the referee where the home team did the worst in 2007 (33% win rate) to the opposite -- the referee after the first nine weeks where the home team has done the best (93% win rate!). If we took out Peter Morelli, the correlation would jump from 0.009 to 0.335 -- so let's see how it shapes up the rest of the year. Considering the correlation between 2006 and 2007 was negative, I am not expecting it to climb by much. But the adventures of Pete Morelli's home win rate continue...

NFL Referee Statistics after Week 9 (after games of 11/3/2008)

2008-11-09T09:47:00.003-05:00

Just a quick update this week -- this includes all the games of week 9, through the game on Monday, November 3, 2008.

No narrative explanation (anything you would like to focus on next time?). Just some statistics this time:

Referee, Penalties accepted per game, Penalty yards accepted per game, Yards per penalty accepted, % of accepted penalties against the visiting team, % of accepted penalty yards against the visiting team, total points scored.

Anderson, Walt 13.0 99 7.59 53.8% 53.6% 36.5
Boger, Jerome 15.0 111 7.38 43.3% 40.3% 43.6
Carey, Mike 9.7 82 8.47 46.6% 45.2% 44.2
Carollo, William 11.8 94 7.99 53.2% 55.5% 40.4
Cheffers, Carl 10.0 86 8.63 41.4% 33.8% 44.9
Coleman, Walt 9.3 73 7.84 63.5% 65.7% 45.9
Corrente, Tony 12.9 121 9.41 49.5% 52.5% 41.4
Green, Scott 10.8 75 6.99 53.5% 53.2% 47.5
Hochuli, Ed 12.9 106 8.21 48.5% 42.2% 48.8
Leavy, Bill 11.1 85 7.64 55.1% 52.9% 45.9
McAulay, Terry 11.9 99 8.37 47.4% 43.8% 45.9
Morelli, Peter 11.0 80 7.26 53.2% 57.1% 51.1
Parry, John 12.7 97 7.62 49.4% 46.2% 42.4
Riveron, Alberto 10.9 95 8.74 43.7% 44.2% 42.8
Steratore, Gene 10.3 80 7.77 56.1% 57.8% 38.5
Triplette, Jeff 15.1 117 7.72 46.3% 40.8% 42.5
Winter, Ron 14.8 121 8.23 48.3% 51.6% 50.4

NFL Referee Statistics: Net Total Points Per Game

2008-11-01T10:34:00.002-05:00

After 8 weeks (on 11/1/2008, just before Week 9 begins), let's take a look at which referees have the highest-scoring games compared to what you would expect from the particular teams on that referee's schedule. Just as team statistics include adjustments for the strength of the opponent, let's adjust the referee statistics by the strength of the two teams involved.

This way, if a referee has a schedule packed with high-scoring teams, we can filter that out in seeing whether his games are higher scoring than usual.

Here we go!

Net Total Points (with team adjustments) as of 11/1/2008:
Ron Winter (+5.4), 51.4 raw total points
Peter Morelli (+4.5), 51.3
Ed Hochuli (+4.3), 47.6
Carl Cheffers (+3.7), 47.5
Terry McAulay, (+3), 46.7
Bill Leavy (+2.9), 47.7

referees where you might consider taking the under if you bet the over/under for total points:

Walt Anderson (-5.5), 38.3
Gene Steratore (-5.2), 38.5
Jeff Triplette (-3.2), 41.9
Tony Corrente (-3.0), 41.1
John Parry (-1.7), 42.4

When we account for team adjustments, the top two remain the same but Bill Leavy falls from third in raw total points to sixth in net total points. This is because three other referees that sneak ahead of him in net total points covered games with teams that overall had lower-scoring games than the average.

Looking at the bottom, the bottom two remain the same but Jeff Triplette leaps from 5th-lowest in raw total points to third-lowest in net total points. This is a combination of how his teams had slightly more than usual total expected points (45.1) and Tony Corrente (44.2) and William Carollo (43) had slightly lower-scoring teams in their games.

No major or drastic differences, though, for the rankings between raw total points and net as compared to the teams involved.

NFL Referee Statistics After Week 8 (Updated 11/1/2008)

2008-11-01T10:10:00.002-05:00

Let's go through some interesting categories for 2008 NFL referee statistics:

Total accepted penalties

Jeff Triplette (15.3) lost most of his lead over Ron Winter (15.1) and Jerome Boger (14.7).

Walt Coleman (9.4) still at the bottom, in front of Scott Green (10.1) and Carl Cheffers (10.2).

Total penalty yards

Ron Winter (127) keeps his lead over Tony Corrente (121) with Jeff Triplette down in third at (118).
Scott Green (75) and Walt Coleman (75) in a virtual tie at the bottom.

Yards per penalty

Tony Corrente (932) again extends his lead over Alberto Riveron (8.7) and Terry McAulay (8.6)

Peter Morelli (7.1) a bit more ahead of Jerome Boger and Scott Green (7.4).

Points per game (no team adjustments)

These are raw numbers, not adjusted for the teams who played in the games.

Ron Winter (51.4) is almost caught by Peter Morelli (51.3) followed by Bill Leavy, Ed Hochuli, and Carl Cheffers (each in the 47.5-47.7 range).

Walt Anderson (38.3) takes over the bottom with Gene Steratore (38.5) close behind. Tony Corrente plummeted to third from 36.5 last week to 41.1 this week. That's what a jolly old week in London for a high-scoring 37-32 game between New Orleans and San Diego will do to your statistics.

Week 9 Cheatsheet

Referee, penalties, penalty yards, yards per penalty, and total points:
Anderson, Walt 13.3 99.1 7.46 38.3
Boger, Jerome 14.7 109.4 7.44 42.9
Carey, Mike 10.6 91.2 8.60 46.4
Carollo, William 13.0 104.4 8.03 41.4
Cheffers, Carl 10.2 80.8 7.95 47.5
Coleman, Walt 9.4 75.0 7.95 45.4
Corrente, Tony 13.0 120.9 9.30 41.1
Green, Scott 10.1 74.6 7.35 45.1
Hochuli, Ed 12.7 105.6 8.30 47.6
Leavy, Bill 12.0 90.0 7.50 47.7
McAulay, Terry 11.1 95.7 8.59 46.7
Morelli, Peter 11.7 83.0 7.11 51.3
Parry, John 12.7 96.9 7.62 42.4
Riveron, Alberto 10.9 95.0 8.74 42.8
Steratore, Gene 10.3 79.6 7.77 38.5
Triplette, Jeff 15.3 117.7 7.70 41.9
Winter, Ron 15.1 127.4 8.42 51.4

NFL Referee Statistics Through Week 7 (updated 10/25/2008)

2008-10-25T13:28:00.002-05:00

Let's go through some interesting categories for 2008 NFL referee statistics:

Total accepted penalties

Jeff Triplette (16.2) still well in front of Ron Winter (15.3) and Jerome Boger (15).

Walt Coleman (9.3) now at the bottom, then Gene Steratore (10) and Carl Cheffers (10.2).

Total penalty yards

Ron Winter (131) takes over with Jeff Triplette (127) falling to second, then Tony Corrente (109).
Walt Coleman (73) at the bottom then Scott Green (77) and Gene Steratore (78).

Yards per penalty

Tony Corrente (9.2) extends his lead over Alberto Riveron (8.8) and Terry McAulay (8.7)

Peter Morelli (7.1) just ahead of Jerome Boger (7.2) and Walt Anderson falls to third (7.3).

Points per game (no team adjustments)

These are raw numbers, not adjusted for the teams who played in the games.

Ron Winter (53.2) takes over the lead from Peter Morelli (51.2) then Bill Leavy (47.7).

Tony Corrente (36.5) takes over from Walt Anderson (37.8) then Gene Steratore (40.9).

Week 6 Cheatsheet

Referee, penalties, penalty yards, yards per penalty, and total points:
Winter, Ron 15.3 131 8.5 53.2
Morelli, Peter 12.4 88 7.1 51.2
Leavy, Bill 12.0 90 7.5 47.7
Hochuli, Ed 12.7 106 8.3 47.6
Cheffers, Carl 10.2 81 8.0 47.5
McAulay, Terry 11.3 98 8.7 46.7
Green, Scott 10.3 77 7.4 46.2
Carey, Mike 11.0 95 8.7 45.0
Coleman, Walt 9.3 73 7.9 44.7
Boger, Jerome 15.0 108 7.2 43.2
Riveron, Alberto 11.4 101 8.8 43.1
Carollo, William 12.7 100 7.9 42.5
Parry, John 12.3 93 7.6 42.5
Triplette, Jeff 16.2 127 7.9 42.3
Steratore, Gene 10.0 78 7.8 40.9
Anderson, Walt 13.2 97 7.3 37.8
Corrente, Tony 11.8 109 9.2 36.5

Continued Gag Rule: NFL Fines Plaxico Burress For Criticizing Referees

2008-10-24T21:59:00.002-05:00

The NFL again imposes its gag rule against players, coaches, and players against criticizing or commenting on NFL referees. Why do they insist on a gag rule and chilling people from commenting and discussing NFL referee performance?

News reports say that Plaxico Burress said that a call against him was one of the worst call he'd ever seen. Also that he is playing his tail off and he wanted the referees to do the same thing. And that a bad call is like a referee just stealing from him.

How is that something that should be fined $20,000?

His defense should be that he was not calling the referees corrupt or questioning their integrity -- he was just expressing his opinion that there was a bad call, which also helped explain Plaxico Burress's own performance and help the fans know what he had done during the game.

Sportswriters should respond to the gag rule by increasing commentary of NFL referee performance. Everyone makes mistakes, why not point them out and discuss them, especially if the NFL uses a harsh gag rule on the players? Are people afraid to upset the NFL?

NFL Referee Correlations between 2007 and 2008 seasons are limited so far

2008-10-18T11:06:00.002-05:00

After only 6 weeks, let's take a look at correlations among the spread of NFL referees who worked the 2007 season and the 2008 season (through 6 weeks).

I'm looking for the correlation among the variations among the referees. So if the number of accepted penalties varies by referees and certain ones call more every year than others, then there will be a correlation when we compare the variations among them.

So far, after just 6 weeks, there are not many strong correlations between the full 2007 season and the first 6 weeks of the 2008 season.

For total penalties, which usually has a strong correlation from one year to the next, it is only 0.021. Total yards is 0.109. Yards per penalty stands at -0.052.

Total points is -0.053. Visiting team points is 0.280. Home team points is -0.239. The home team win rate is at 0.099. Let's see how the correlations shape up as the season goes on.

NFL Referee Statistics through week 6 (after 10/13/2008)

2008-10-18T10:45:00.004-05:00

Let's go through some interesting categories for 2008 NFL referee statistics:

Total accepted penalties

Jeff Triplette (17.4) way in front of Ron Winter (14.2) and Peter Morelli (14).

Gene Steratore (99) at the bottom, trailed by Walt Coleman (9.3) and Carl Cheffers (9.3).

Total penalty yards

Jeff Triplette (138) of course on top followed by Ron Winter (121) and Ed Hochuli (112).

Gene Steratore (72) virtually tied with Walt Anderson and Walt Coleman (73).

Yards per penalty

Tony Corrente (9.2) edged ahead of Terry McAulay (8.9) and Mike Carey (8.7).

Walt Anderson (6.6) at the bottom, below Peter Morelli (6.8) and Jerome Boger (7.2).

Points per game (no team adjustments)

These are raw numbers, not adjusted for the teams who played in the games.

Peter Morelli (54.8) on top of Ron Winter (54.2) and Terry McAulay (51).

Walt Anderson (36.2) on the bottom with Tony Corrente (36.5) breathing down his neck, followed by Carl Cheffers (39.2).

Week 6 Cheatsheet

Referee, penalties, penalty yards, yards per penalty, and total points:

Anderson, Walt 11.0 73.0 6.6 36.2
Boger, Jerome 13.8 100.0 7.2 46.0
Carey, Mike 11.0 95.3 8.7 45.0
Carollo, William 13.4 105.8 7.9 41.2
Cheffers, Carl 9.6 78.0 8.1 39.2
Coleman, Walt 9.3 73.3 7.9 44.7
Corrente, Tony 11.8 108.7 9.2 36.5
Green, Scott 11.4 85.4 7.5 49.4
Hochuli, Ed 13.7 111.5 8.2 47.5
Leavy, Bill 11.8 89.0 7.5 49.2
McAulay, Terry 11.8 105.4 8.9 51.0
Morelli, Peter 14.0 95.0 6.8 54.8
Parry, John 12.2 94.4 7.7 41.4
Riveron, Alberto 11.2 92.2 8.3 42.3
Steratore, Gene 9.0 71.5 7.9 40.3
Triplette, Jeff 17.4 138.4 8.0 43.4
Winter, Ron 14.2 121.2 8.5 54.2

NFL Continues Gag Rule -- Fining Players For Criticizing Officials

2008-10-18T10:23:00.002-05:00

The NFL issued $20,000 fines to NFL players Denver Broncos Dre' Bly and Miami Dolphins Joey Porter for making comments that were critical of NFL referees.

Joey Porter said that he thought his team won the game, actually, "but they kept getting calls." I wonder if that is considered referee criticism. Sounds like just commenting on how the other team got calls -- he isn't saying that the calls were wrong.

Dre' Bly said that after getting some favorable calls in other games, "I guess they've been evaluating us and say we won games we shouldn't have won. So, I guess they're going to get a call against us." I wonder whether there's an argument that Dre' Bly is just applying an unfounded statistical approach to probabilities and commenting that a call will happen at some point that under an illogical approach, perhaps things will even out and go against his team.

Anyway, why does the NFL have a gag rule against commenting on NFL referees? It is unfair to gag the coaches, players, and owners. The sportswriters should focus harder on criticizing and commenting on NFL referees -- come on, save the players who are gagged and can't say anything. Say it for them and let the players save their money by staying quiet!

NFL 2008 Referee Statistics through week 5 (10/6/2008)

2008-10-12T00:10:00.002-05:00

Here we go with NFL referee statistics for 2008 through week 5 (through October 6, 2008)!

Post a comment with your ideas, criticisms, and suggestions.

Of several potential areas to track, let's start off with the total number of accepted penalties per game and the total number of accepted penalty yards per game. We can also look at the average penalty yards per accepted penalty (which referees have large-yardage penalties?)

Total accepted penalties
Jeff Triplette continues to obliterate the competition with 19 penalties per game! Next are Ed Hochuli (15.4), Ron Winter (14.8), and Wililam Carollo (14.3).
At the bottom, Walt Coleman (7.8) is followed by Gene Steratore (9.2) and Carl Cheffers (9.3)

Total penalty yards
Not a surprise that Jeff Triplette is also burning up the scoreboard on total penalty yards (149 per game). Next are Ron Winter (135), Ed Hochuli (127), and Terry McAulay (118).
At the bottom, Walt Coleman (62) then a few clustered around 72-76: Peter Morelli, Walt Anderson, Carl Cheffers, and Gene Steratore.

Yards per penalty
Who has the largest yards per penalty? Terry McAulay clings to a slender lead at 9.2 per penalty followed by Ron Winter (9.1) and Mike Carey (8.7).
At the bottom: Walt Anderson (6.6) and Peter Morelli (6.8)

Points per game
We have not done adjustments for the teams in each game, so here are some raw numbers, no doubt affected by the teams assigned to the referees:
Highest points per game is Peter Morelli (55), Terry McAulay (54.5), Bill Leavy (51.5) and Ron Winter (51.3).
At the bottom, Walt Anderson (36.2), Tony Corrente (39.4), and John Parry (39.5).

Week 5 Cheat Sheet
For this week's cheat sheet, we list the referee along with total accepted penalties, total penalty yards, yards per penalty, and total points per game. Doubt you'll see these posted on your television during the game, although I think they should be!

Ref Ttlpen Ttlyd AvgPen Ttl pts
Anderson, Walt 11.0 73 6.6 36.2
Boger, Jerome 13.5 96 7.1 49.0
Carey, Mike 11.0 95 8.7 45.0
Carollo, William 14.3 108 7.6 41.3
Cheffers, Carl 9.3 74 7.9 41.5
Coleman, Walt 7.8 62 7.9 46.4
Corrente, Tony 11.8 91 7.7 39.4
Green, Scott 11.4 85 7.5 49.4
Hochuli, Ed 15.4 127 8.2 45.6
Leavy, Bill 12.5 88 7.0 51.5
McAulay, Terry 12.8 118 9.2 54.5
Morelli, Peter 10.7 72 6.8 55.0
Parry, John 11.5 95 8.2 39.5
Riveron, Alberto 11.0 90 8.2 42.4
Steratore, Gene 9.2 76 8.3 40.4
Triplette, Jeff 19.0 149 7.9 43.3
Winter, Ron 14.8 135 9.1 51.3

NFL Continues To Enforce Gag Rule -- Who Will Critique Referees?

2008-09-28T14:48:00.002-05:00

The NFL continues its harsh gag rule against owners, coaches, and players from saying anything negative about referees, even if it's just a honest comment that a referee made a mistake in the game. I can understand a rule that bans any horrible accusation that a referee is intentionally cheating, but why the gag rule where you can't even say the truth -- that a referee made a human error and one of his calls was a mistake?

With the gag rule against NFL players, owners, and coaches, there should be more discussion and criticism by sportswriters. Or does the NFL have an unwritten gag rule against sportswriters? Do they feel like they have to stay on the NFL's good side to keep getting access to the players and coaches?

Let's look at the gag rule so far.

Jerry Jones commented on Ed Hochuli's mistake in the Broncos-Chargers game. The NFL fined Cowboys owner Jerry Jones $25,000. Saints coach Sean Payton criticized referees after a 34-32 loss to the Denver Broncos and the NFL fined him $15,000. Chargers coach Norv Turner was nearly fined for saying that Ed Hochuli's mistake was unacceptable -- only barely escaping a fine because he limited it to one word, did not make any other negative remarks, and said no comment when he was asked about it by reporters later that week. Yes, the NFL rewards people financially for saying no comment to reporters.

(Sean Payton was complaining about an offsides penalty that the referees did not call against the Broncos Jamie Winbown.)

According to profootballtalk.com, the NFL will now only impose fines if there is criticism of the integrity of officiating, even though the NFL constitution prohibits all criticism, regardless of whether it touches on integrity. That doesn't make sense, because Cowboys owner Jerry Jones only criticized how Ed Hochuli's crew calls many penalties and is highly criticized -- I don't see any attack on his integrity.

Sean Payton said therew as a violation that should have been called but wasn't and it's not a judgment call. I don't see any attack on anybody's integrity, just a missed call.

If the rules are unclear, the bottom line is that everyone in the NFL will be quiet rather than risk tens of thousands of dollars. Where are the sportswriters to fill in the gap of the gagged coaches, players, and owners?

Ed Hochuli Again In The Spotlight

2008-09-28T14:38:00.002-05:00

Ed Hochuli was already in the hot seat for his call in the game between the Denver Broncos and San Diego Chargers. Now, another controversial call in the game between the Atlanta Falcons and Carolina Panthers. Julius Peppers hit Falcons quarterback Matt Ryan and referee Ed Hochuli called it roughing the passer for a helmet-to-helmet hit, although replays show that it was not a good call. It's controversial because it negated what would have been an interception by the Carolina Panthers that they returned for a touchdown.

Do the referee tendencies from the first three weeks of 2008 and the 2007 season show anything?

One theory is that some referees unconsciously help the home team more than others. That doesn't really explain Ed Hochuli's two calls because one helped the home team (the Broncos) and one helped the visiting team (the Falcons).

Another theory is that some referees call a game that helps the offense more and on average that would tend to lead to higher scoring games. Ed Hochuli's two calls each helped the offense. He threw the flag before he knew the interception would be returned for a touchdown so it might be consistent with higher-scoring games. Over the first 3 weeks of 2008, Ed Hochuli is 3rd of 17 in penalties per game and 8th of 17 in total points per game. In 2007, he was 5th of 17 in penalties per game and 3rd of 17 in total points per game.

The statistics only slightly suggest perhaps a tendency to help the offense. Might just be bad calls by chance by Ed Hochuli.

NFL 2008 Referee Statistics through Week 3 (9/22/2008)

2008-09-27T10:55:00.002-05:00

Let's kick off our 2008 NFL referee statistics with analysis through week 3 (through September 22, 2008)! Send your questions, ideas, suggestions in comments to this posting.

Of several potential areas to track, let's start off with the total number of accepted penalties per game and the total number of accepted penalty yards per game. We can also look at the average penalty yards per accepted penalty (which referees have large-yardage penalties?)

Total accepted penalties
Jeff Triplette is obliterating the competition through the first three weeks of the season, averaging 18 penalties per game! Next four are Jerome Boger (14.5), Ed Hochuli (14.3), and Tony Corrente and John Parry (tied with 14.0).
At the bottom, Carl Cheffers and Gene Steratore are tied with 8.7 per game.

Total penalty yards
Not a surprise that Jeff Triplette is also burning up the scoreboard on total penalty yards (137 per game). Terry McAulay follows at 118 per game then a clustering of six referees at 107-112 per game.
At the bottom, Carl Cheffers is low-man with 61 per game followed by Scott Green (70) and Gene Steratore (72).

Yards per penalty
Who has the largest yards per penalty? Terry McAulay is far in the lead (9.8 per penalty) followed by Mike Carey (8.5) and Gene Steratore (8.3).
At the bottom are Walt Anderson (6.5) and Bill Leavy (6.9).

Points per game
We have not done adjustments for the teams in each game (it's a bit early in the season to do team adjustments), so here are some raw numbers, no doubt affected by the teams assigned to the referees:
Highest points per game is Terry McAulay (66.5) and Peter Morelli (59). At the bottom are Tony Corrente (31.3), John Parry (33.7), and Walt Anderson (34).

Week 3 Cheat Sheet
For this week's cheat sheet, we list the referee followed by: rank in total accepted penalties (1st is largest), rank in total penalty yards (1st is largest), rank in points per penalty (1st is largest), and total points per game. Doubt you'll see these posted on your television during the game, although I think they should be!

Walt Anderson (10, 12, 17, 34.0)
Jerome Boger (2, 7, 10, 53.0)
Mike Carey (7, 6, 2, 38.5)
William Carollo (11, 10, 12, 47.3)
Carl Cheffers (16, 17, 14, 38.3)
Walt Coleman (14, 13, 11, 53.7)
Tony Corrente (4, 5, 5, 31.3)
Scott Green (15, 16, 15, 38.3)
Ed Hochuli (3, 3, 6, 46.0)
Bill Leavy (8, 11, 16, 51.0)
Terry McAulay (12, 2, 1, 66.5)
Peter Morelli (13, 14, 13, 59.0)
John Parry (5, 4, 4, 33.7)
Alberto Riveron (9, 9, 8, 38.7)
Gene Steratore (17, 15, 3, 39.7)
Jeff Triplette (1, 1, 9, 41.7)
Ron Winter (6, 8, 7, 52.7)

Jacksonville Jaguars, Indianapolis Colts, and Side Judge Rick Patterson

2008-09-23T06:29:00.002-05:00

Can someone fill me in on the controversy with side judge Rick Patterson and his performance in the Jaguars-Colts game in week 3 on September 21, 2008.

Browsing the web, I see some comments about not calling pass interference on an interception that Rashean Mathis returned for a TD after grabbing Marvin Harrison's jersey (but this might not have been by side judge Rick Patterson).

Is it perhaps in the fourth quarter when David Garrard threw a short pass for wide receiver Reggie Williams and an official called pass interference on Freddie Keiaho of the Colts? Was that Rick Patterson's call? I don't think that would be the biggest controversy because the NFL told Tony Dungy that it was a good call, but Tony Dungy would not reveal the blown calls, no doubt because the NFL has a gag rule that silences coaches from commenting on referee mistakes.

Can someone post a comment that explains what call was the controversial one by side judge Rick Patterson?

Week 3 NFL Referee Schedule

2008-09-20T05:49:00.001-05:00

Please post comments if you see reports on which referee will be covering which game in week 3.

Cleveland Browns at Baltimore Ravens: Ed Hochuli (according to Ken Murray at the Baltimore Sun).
Tampa Bay Buccaneers at Chicago Bears: Tony Corrente (according to Brad Biggs at the Chicago Sun-Times).
Cincinnati Bengals at New York Giants: Jeff Triplette

Hochuli Admits Mistake, Owner Comments On Referee's Performance

2008-09-16T06:24:00.002-05:00

Let's take a look at what for NFL standards was unsual about Ed Hochuli's mistake in the San Diego Chargers and Denver Broncos game in week two (Sunday, September 14, 2008).

Is it unusual for a referee to make a mistake? No.

Is it unusual for the NFL to acknowledge publicly that a referee made a mistake? Sadly, the answer is yes! It is unusual for the NFL to admit to the public that any of its referees actually made a mistake at any point during a game. The NFL usually admits privately to one of the teams about mistakes, but strangely does not admit it to the public most of the time. Why not? Can you think of a reason why the NFL is so secretive about human error by any of its referees? Let's use blogs and message boards to raise the level of discussion and point out errors by referees. Referees are human and they make mistakes -- mistakes do not necessarily mean that the referee is trying to cheat any team. Scientists talk all the time about unconscious bias (perhaps swayed by the cheering fans?) -- why can't we talk about it?

Is it unusual for the NFL to discuss grading the referees? Yes, that is also unusual. The NFL spokesman Greg Aiello said that officials are held accountable for their calls and that Ed Hochuli "has been an outstanding official for many years, but he will be marked down for this call."

Is it unusual for an NFL coach or owner to comment on referee performance? Yes, very unusual. This is because the NFL has a policy of issuing fines against coaches, players, and owners who talk about referees. With this gag order, sportswriters and bloggers should pick up the slack and have intelligent discussions about referee errors.

Denver coach Mike Shanahan said Ed Hochuli's crew was the best in the last 20 crews he graded (yes, the coaches grade the referees and keep secret their opinions from the public!). Cowboys owner Jerry Jones said Ed Hochuli "gets a lot of criticism. He's a highly criticized official in the NFL." Wow, owners and coaches actually commenting on referee performance!

Post some comments on whether there should be more coverage of referee errors and performance -- and whether the NFL is wrong for gagging people from commenting on referee mistakes.

Mistakes happen, the gag order seems just plain un-American.

2008 NFL Fantasy Football: Referee Choices

2008-08-24T07:34:00.002-05:00

Let's discuss our recommendations for your fantasy football draft if you were playing in a fantasy football referee league. I'm not sure how you would run a fantasy league for NFL referees, but maybe you would draft referees and then rank them by total penalties accepted per game, total penalty yards per game, average penalty yards per penalty, and home team win rate. You should keep tabs all year long rather than have them compete head-to-head every week because the NFL does not tell you which referees will have a bye week. That makes it difficult to know which referee to choose (unless you let each team choose 2 referees and hope one of the two doesn't have a bye week).

Our recommendations for the 2008 season. These predictions might not come true, so try not to laugh too hard when you look at these at the end of the season.

Accepted penalties per game:

1. Ron Winter (two-time league leader!)

2. Tony Corrente

3. Jerome Boger

4. Ed Hochuli

sleeper pick: Walt Anderson (unimpressive in 2006 but 3rd in 2007)

Accepted penalty yards per game:

1. Ron Winter

2. Tony Corrente

3. Terry McAulay

4. John Parry

sleeper pick: Ed Hochuli (league-leader in 2006 but mediocre in 2007)

Average penalty yards per penalty:

1. Gerry Austin (two-time league leader!)

2. Scott Green

3. Terry McAulay

4. John Parry

sleeper pick: Ed Hochuli (big year in 2007 but mediocre in 2006)

Home win rate: this one is very hard to predict because the 2006 and 2007 rates did not match up well by referee. A great deal probably depends on how the NFL assigns the teams for the referee's games. It's as if the quality of the teams playing have more influence on the game's result than which referee was assigned!

Here are some laughable wild guesses:

1. John Parry

2. Terry McAulay

3. Jerome Boger

Accepted Penalty Yards per week, 2007 season

2008-08-24T07:20:00.000-05:00

Time to get ready for the 2008 NFL Season. Let's take a short look at the penalty yards accepted per week in the 2007 season. I expected to see lots of penalty yards the first two weeks as the teams get out of pre-season form and then perhaps less penalties toward the end of the season in case players by then have figured out how the refs call the games.

But actually, the numbers show the biggest weeks for accepted penalty yards were in the middle of the season -- week 8 and week 9. Although the lowest accepted penalty yards were close to the end of the season (weeks 14 and 15), the final week (week 17) did have a bunch of penalty yards. Maybe just random statistical variation because it is such a small sample size. Or maybe some influence of starters resting in the last week and using players with less practice/experience?

1: 89.6
2: 96.3
3: 84.6
4: 87.1
5: 91.2
6: 91.4
7: 87.7
8: 106.8
9: 112.0
10: 97.4
11: 94.3
12: 79.2
13: 96.1
14: 76.3
15: 72.3
16: 81.1
17: 92.0

Farewell Larry Nemmers and Gerald Austin; Hello Carl Cheffers and Al Riveron

2008-04-12T12:02:00.002-05:00

The Courier News is reporting that after 17 years as a crew chief, Larry Nemmers is retiring from being an NFL referee (although he will become the NFL's replay director) and after 18 years as a crew chief, Gerald Austin is retiring from NFL refereeing.

According to the article, NFL officiating director Mike Pereira confirmed that Carl Cheffers and Al Riveron will be the new referees to replace them next season.

Let's look back with nostalgia on Larry Nemmers and Gerald Austin in 2007.

Favorites did not do that well in Larry Nemmers's games, winning 67% of the time rather than our estimate of 79% so they did 12% worse than expected. Second-worst of the NFL referees by our estimation.

Gerald Austin won the title in 2007 for the lowest number of accepted penalties per game. He won't be coming back to defend his title. Pete Morelli becomes the favorite to step up in 2008.

Gerald Austin and Larry Nemmers were right at the top in yards per penalty -- Gerald Austin won the title with 9.0 per penalty with Larry Nemmers in third at 8.4 per penalty. Scott Green has a chance to break through in 2008 and claim the top spot.

If only somebody would set up an NFL referee fantasy league! It would be hard, though, because the NFL does not announce which referees are playing which games or even which referees have a bye week.

NFL Rule Changes for 2008 May Reduce Penalties

2008-04-05T08:55:00.002-05:00

Many newspapers are reporting on changes in the NFL rules. Strange, there doesn't seem to be an announcement about this from the NFL itself on the NFL web site. I guess they expect fans to catch up by reading the newspapers and hearing second-hand.

Rule changes that may affect the number of penalties include:

No 5-yard penalty for incidental facemask infractions.
Allowing one defensive player to have a communicating device with the coaches.

According to AP football writer Barry Wilner, allowing a defender to communicate with the coaches might lead to less penalties. According to the chairman of the Arena Football League's rules and competition committee, when they changed the rules to allow a defender to communicate with the coaches, there were more defensive stops and less penalties. Barry Wilner wrote that there was, surprisingly, an increase in scoring.

If that's correct, there might be slightly less penalties called this year. But we might still have the same distribution of penalties among the referee crews (the ones that regularly call more penalties might still be near the tops in penalties, although calling a little less than last year).

Post your thoughts and predictions for next year's penalty rate.

Sabermetrics and NFL Referee Statistics: Home Field Advantage

2008-03-16T10:49:00.002-05:00

Browsing the web, someone has posted on his blog about sabermetrics and home field advantage, suggesting that perhaps statistical analysis might shed light on whether a great deal of home field advantage is based on referees' unconscious bias toward the home team.
http://sabermetricresearch.blogspot.com/2007/02/how-much-of-home-field-advantage-is.html

Post a blog comment if you have some ideas for how to research this for NFL statistics.

I'll take a look through the statistics that I've been tracking in 2006 and 2007 to see what I can come up with. Maybe if someone is tracking field goal percentage by home and visiting teams that would help. Or better yet, adjusted-field-goal-percentage to even out how some field goals are harder to make than others.

Or to make things even easier, maybe if someone has kept track of extra point conversion percentage by home and visiting teams for a few NFL seasons?

Accepted Penalties by Week, 2007 NFL Season

2008-02-10T19:00:00.000-05:00

We crunched the numbers for the number of accepted penalties per game by week during the 2007 season. This doesn't cover other seasons so it is just a limited look. We expected to see lots of penalties the first few weeks (while the players got used to rule changes or worked out the pre-season sloppiness), but that doesn't seem to be the case.

The first 7 weeks were roughly around 11.6 per game, then it increased in weeks 8-10, then more or less settled to a level slightly lower than the first 7 weeks for the remainder of the season. Any thoughts?

Weeks 1-7: 11.56 accepted penalties per game (ranging from 11.25 to 12.07)
Weeks 8-10: 13.29 per game (from 13.08 to 13.43)
Weeks 11-17: 10.69 per game (from 9.56 to 12.25)
1: 11.25
2: 11.75
3: 11.38
4: 12.07
5: 11.36
6: 11.62
7: 11.50
8: 13.08
9: 13.36
10: 13.43
11: 11.25
12: 10.06
13: 12.25
14: 10.50
15: 9.56
16: 10.00
17: 11.19

Super Bowl 42: Giants and Patriots Postscript

2008-02-10T18:46:00.001-05:00

Before Super Bowl 42, we took a look at what type of games the Giants and Patriots generally did well in. Now that we went out on a limb (not really, we didn't make any bold predictions), let's take a look at how the game turned out.

The Giants did better in games with a large number of penalties while the Patriots were the opposite. This didn't happen in the Super Bowl, though, because there were 9 total penalties (around 70% of regular season games had more penalties), so you would think this would favor the Patriots.

The Patriots do worse when a larger percent of penalties are called against them. This is not too surprising. But in any case, with 5 penalties out of 9 called against the Patriots, this did hold up in the Super Bowl (but not a very surprising fact).

The Patriots did not do that well when it had lots of penalties called against it (regardless of how many were called in total). The Patriots had 5 penalties, which was pretty much the median for them in the regular season, so this factor did not prove anything.

The Giants do a bit worse when they have a large number of penalty yards called against them (a bigger effect than the Patriots had). The Giants had 36 penalty yards against them in the Super Bowl. That was close to the median for them in the regular season, so this factor did not prove anything.

Before the game, we had said:

For the Giants, hope the game has a large number of penalties and a low number of penalty yards called against the Giants (although the number of penalties is not that important).

For the Patriots, hope the game has have a lower percent of the penalties called against the Patriots and that there is a low number of penalties against the Patriots.

Now that the game is over, these suggestions didn't really help much. One of them (number of penalties) did not really pan out while the other three didn't really get tested because the game was close to the median. Oh well, maybe next year we will have a bigger trend and a chance to test it out in the next Super Bowl!

Super Bowl 42: Giants and Patriots Trends By Game Statistics

2008-02-03T09:55:00.000-05:00

Let us take a look at the types of statistics that appear in the games where the Giants and Patriots do the best. This does not help us predict a game before it starts, because we won't know how the game's actual statistics shape up until the game is underway. But maybe it will give you some interesting analysis to refer to during the game. In parentheses are the correlation figures for that statistic to either net points or Giants victories. No correlation figures for Patriots odds of winning because they won all their games.

Total penalties in the game: Giants do better with a large number of penalties called in the game. (0.168 by net points and 0.135 by win) while the Patriots do better with a lower number of penalties called in a game (-0.133 by net points).

Total penalty yards: little correlation.

Average penalty yards per penalty: we blogged before the semifinals about how the Giants typically do better in games where there are lower average yards per penalty. The Patriots have a similar trend. For the Giants, a negative trend (-0.161 by net points and -0.432 by win) while the Patriots also do better with a low average yards per penalty (-0.224 by net points).

Percent penalties called against the team: it seems like common sense that a team does better when the percent of penalties called against it is lower. But the Giants seem to be less affected by this factor (-0.171 by net points and -0.313 by wins) than the Patriots (-0.365 by net points).

Percent penalty yards called against the team: for both teams, they somewhat equally prefer to have a lower pecentage of penalty yards called against it. (Giants net points -0.383; Giants wins -0.493; Patriots net points -0.460).

Penalties against the team (regardless of how many total penalties are called): the Giants seem to do only a little bit worse as more penalties are called against it (-0.043 by net points and -0.152 by wins) while the Patriots do worse as it has more penalties against it (-0.289 by net points).

Penalty yards against the team: the Giants seem to do worse as more penalty yards are called against it (-0.238 by net points and -0.399 by wins) than the Patriots (-0.202 by net points).

Conclusion: We do not have a big enough sample to draw any strong conclusions. But if you are interested even in very weak suggestions, then you can say.

For the Giants, hope the game has a large number of penalties and a low number of penalty yards called against the Giants (although the number of penalties is not that important).

For the Patriots, hope the game has have a lower percent of the penalties called against the Patriots and that there is a low number of penalties against the Patriots.

Let's check in on these weak trends after we can look up the final Super Bowl statistics.

Super Bowl 42: Giants and Patriots Season Trends by Referee

2008-02-03T09:30:00.000-05:00

Let's take a look at the regular season performance of the New York Giants and the New England Patriots. We are looking into the teams to better with certain types of referees and worse with other types of referees. We do not have enough games to draw solid conclusions -- but we have an entire season of 16 games, even though 16 is a small sample size.

We are working with what we have -- so let's ignore the strength of the opponent, the weather, and other very important factors. We are going to ignore all those important factors and just focus on correlations between certain referee statistics.

Let's see if there is a correlation between the net points (by how many points the team won) along with a correlation with the Giants' wins. We can't search for a correlation with the Patriots' victories because, well, they won all their games! We are comparing the result of each game with the season-long statistic for the referee who covered that game. For example, in week 8 the New York Giants beat the Miami Dolphins 13-10 in a game that Gerald Austin refereed. So we can compare the Giants win that week with how the referee who covered the game averaged 8.9 penalties per game over the course of the regular season.

Total penalties accepted per game: the Patriots won by a bigger margin with referees who had smaller total penalties per game (-0.387 correlation). The Giants had better net points with referees with larger total penalties per game (-0.151) and won more often with referees with larger total penalties per game (0.118). So, this suggests a referee averaging more penalties per game is better for the Giants. Interesting, but Mike Carey was 9th out of 17 referees so he is pretty much middle of the pack.

Total penalty yards accepted per game: Patriots better with low penalty yards (-0.321) while Giants better with high penalty yards (0.169 for net points; 0.173 for wins). Mike Carey was 11th out of 17, so slightly below average for total penalty yards per game. Slight advantage perhaps to the Patriots.

Average yards per penalty: Patriots like higher yards per penalty (0.162) while Giants somewhat also prefer higher yards per penalty (0.011 for net points; 0.142 for wins). Mike Carey is 14th out of 17 in average yards per penalty.

Total points per game: Patriots somewhat like lower total points per game (-0.154) while Giants very much like lower total points per game (-0.364 for net points; -0.396 for wins). Mike Carey is 6th of 17 for total points per game, so this seems like a slight advantage perhaps to the Patriots.

So if we look for trends by the head referee's season-long statistics, we come up with perhaps a slight advantage to the Patriots. But this is weaker than usual because the Super Bowl has a mixed crew of officials who did not work together in the regular season. So Mike Carey's statistics might not apply for the Super Bowl's mixed-crew.

Super Bowl 42 Referee Mike Carey Great for Favorites

2008-01-30T23:15:00.000-05:00

The referee for Super Bowl 42 between the Giants and Patriots is Mike Carey. He will have an all-star group of officials working with him that is mixture of officials from other referees' regular season crews.

How does he and the referee crews from which the Super Bowl officials come from look for favorites?

To study this, we had to assume a baseline of what makes a favorite. We looked at the actual season results using the footballoutsiders DVOA difference for the visiting and home teams. We made a model of the overall expected wins for the favorites in each of the games and added up the expected and actual wins.

Mike Carey comes out tops out of the 17 referees for the winning percentage for favorites and for the difference between the expected winning percentage and actual winning percentage for favorites.

Favorites won 93% of Mike Carey's games in the regular season, far and away the best. The next best was down at 88% for Ed Hochuli.

Favorites did 17% better than expected in Mike Carey's games (93% winning rate as opposed to the expected 76%). That was tops for the 17 referees, with Bill Leavy coming in second at 14% (favorites won 82% as opposed to the expected 68%).

Let's take a look at the percent boost that favorites received above the expected winning percentage for the regular season crews from which the other officials (other than Mike Carey) come.

Bill Leavy was 2nd best of 17 for favorites at 14% above expected (82% actual, 68% expected).
Ed Hochuli was 5th at 8% above expected (88% actual, 79% expected)
Scott Green was 11th at -1% (73% actual, 75% expected)
Gerald Austin was 13th at -5% (69% actual, 73% expected)
John Parry was 17th and last at -12% (60% actual, 72% expected)

Do these numbers really mean anything at all? Perhaps some referees call the game in a standard kind of way (which would help the favorites because they are the better team) while other referees call a more haphazard game or use their own pecular interpretation of the rules, which might hurt the favorites? Post a comment and of course, feel free to say that you think we are completely out of it with this proposed statistic!

All we do is crunch the numbers, it is up to you to decide whether the numbers are really worth anything. But we do hope you appreciate our number-crunching. We seem to be offering statistics and analysis that hardly anyone else is offering!

By the way, the regular season DVOA difference between the Patriots and Giants was 52%. That is huge. When one team had a 50% or more advantage over the other team in the regular season, the favorites went 20-1. Maybe you can argue that the Giants' playoff form means the regular season DVOA is not a good reflection, but it does not look so great from the DVOA standpoint. Then again, the Giants have bucked the trend. When they visited Dallas, Dallas had over 20% better DVOA in the regular season. Home teams with 20-30% DVOA advantage went 24-4 in the regular season (winning 86% of their games), yet the visiting Giants won anyway.

Super Bowl Giants-Patriots: Referee Statistics

2008-01-27T08:59:00.000-05:00

In this post, we will take a look at the number of penalties called per game, total points per game, and the two teams' experience with the different parts of the Super Bowl crew. We track penalty statistics by the entire referee crew, not by the particular individual in that crew. So let us take a look at how the entire referee crew that each official was a part of did in the regular season:

Referee: Mike Carey (Carey)
Umpire: Tony Michalek (Parry)
Head linesman: Gary Slaughter (Leavy)
Line judge: Carl Johnson (Austin)
Field judge: Boris Cheek (Green)
Side judge: Larry Rose (Green)
Back judge: Scott Helverson (Hochuli)

By the way, there were 17 referee crews in the 2007 regular season.
Referee: (Carey) -- 9th in total penalties, 6th in total points, NE 2-0, NYG 0-1.
Umpire: (Parry) -- 7th in total penalties, 7th in total points, NE 1-0.
Head linesman: (Leavy) -- 6th in total penalties, 14th in total points, NYG 1-0.
Line judge: (Austin) -- 17th and last in total penalties, 5th in total points, NYG 1-0.
Field judge and side judge: (Green) -- 11th in total penalties, 4th in total points, NE 1-0.
Back judge: (Hochuli) -- 5th in total penalties, 3rd in total points, NE 1-0, NYG 0-1.

If you average all of the crew members equally, you'd come out with 11.2 penalties per game which would be 10th if it were a regular season crew. You'd come out with 44.7 total points per game, which would have been 7th.

In the 2007 regular season, New England had experience with 5 of the 7 officials (one of them twice) and the Giants had experience with 4 of the 7 officials. Advantage: New England Patriots.

Our next project if we get time will be to assign a rating for each referee crew about how good they were for favorites -- or whether there was a greater chance of upsets in their games. All we need to crunch these numbers is create a model to identify which team is the favorite and by how much, then to compare the game results and add up the season-long totals for each crew(!)

Super Bowl Giants-Patriots: Mike Carey's All-Star Crew

2008-01-22T19:18:00.000-05:00

Several bloggers are reporting who is on the Super Bowl All-Star crew (if you want to know which bloggers and posters are reporting this, just search on google).

The NFL usually combines officials from various referee crews for the Super Bowl. As best I could, I've put in parentheses the last name of the head referee that the particular official worked with during the NFL regular season.

Referee: Mike Carey (Carey)
Umpire: Tony Michalek (Parry)
Head linesman: Gary Slaughter (Leavy)
Line judge: Carl Johnson (Austin)
Field judge: Boris Cheek (Green)
Side judge: Larry Rose (Green)
Back judge: Scott Helverson (Hochuli)

In a few days, I will try to take a look at the overall referee statistics for the various referee crews that the officials usually worked on. I will also try to take a closer look at Mike Carey's regular season statistics, in case the crew somehow functions similar to how his regular season crew did. (Maybe the head referee to some degree sets the tone for the rest of the crew?)

Why Not Give Back Time After Replay Official's Challenges?

2008-01-21T17:55:00.000-05:00

In the Chargers-Patriots game and the Giants-Packers game, there were challenges by the replay booth assistants that seemed to cost the offense time.

In the Chargers-Patriots game, with 1:20 left in the 2nd quarter, Darren Sproles ran up the middle for 26 yards. The Chargers got up to the line and were about to snap the ball. The assistant challenged the play and they upheld the ruling on the field -- he did not fumble the ball. The ref started the clock and the Chargers lost time while doing a second pre-snap read. The play started 46 seconds after the previous play started.

In the Giants-Packers game, with 1:59 left in the 4th quarter, Eli Manning completed a short pass to Steve Smith for 14 yards. The Giants got up to the line and were about to snap the ball. The assistant challenged the play and they overturned the ruling on the field -- ruling instead that he did not make a first down. The ref started the clock and the Giants lost time while doing a second pre-snap read. The next play started 42 seconds after the previous play started.

In each case, it seemed that if the assistant had not called for a review, they would've snapped the ball in 1-2 seconds, not requiring the additional 10-15 seconds of pre-snap preparation. Do you agree?

Why can't the referees either give back the time that ran off during pre-snap preparation before the assistant buzzed down for a review -- or why can't the refs say that because the offense was about to snap the ball, they would not wind the clock for that particular play until the offense gets out of its huddle and is ready to snap the ball.

That way, the assistant still gets to wait to the very last second pre-snap to buzz down for a review without costing the offense an extra 10-15 seconds for having to do its pre-snap preparation twice.

The lost time seemed to put the Chargers in a more difficult spot (1st and 10 from the NE 31 with two timeouts and 34 seconds left rather than 45-50 seconds) and the Giants too (3rd and 1 from the GB 39 with no timeouts and 1:17 left rather than 1:30 or 1:35).

Super Bowl: Giants and Packers with Mike Carey

2008-01-21T17:02:00.000-05:00

Super Bowl 2008: New York Giants against the New England Patriots. Several newspapers are reporting that Mike Carey will be the referee. They are taking the angle that this is the first time an African-American will be the referee in a Super Bowl. We're focused on statistics of on-field performance, as opposed to these other angles. Let's take a look at our initial view of some of Mike Carey's statistics from the 2007 NFL regular season.

In the playoffs, the NFL usually mixes together members of different referee crews, so Mike Carey's regular season statistics might not be that important for the Super Bowl. Also, both teams have a bye week to prepare so it's not the usual type of game preparation.

On top of all that, the game is played at a neutral site so it is hard to think that regular season statistics about a potential bias toward or against the home team would play out in the Super Bowl.

Some initial statistics about Mike Carey -- we will take another look at Mike Carey's statistics as we get closer to the Super Bowl and will try to analyze the other members of the Super Bowl referee crew when we find out who they are.

In the regular season, Mike was a good referee for visiting teams. Home teams only won 40% of their games with Mike's crew, which was second-worst of the 17 referee crews.

Mike was 6th (of 17) in total points scored per game (45.0), 4th in visitors' points (23.5) and 12th in home team points (21.5).

Mike was middle of the pack (9th) in penalties per game at 11.8. Ranked 10th in penalty yards per game (90 yards per game). Ranked near the bottom (14th) in average penalty yards per penalty at 7.6. Mike was tied for the highest in the percent of his games where the visiting team had more penalties called than the home team (70%). He is not the only referee where most games had more penalties called against the visiting team yet the visiting teams did well in his games. The same quality of usually more penalties called against the visiting teams yet the visiting teams nevertheless usually winning the games also applied to Ron Winter this year.

New England is more familiar with Mike Carey, having had him in their week 6 victory 48-27 over Dallas and their week 17 victory 38-35 over the Giants. The Giants only had him once, in their game with the Patriots.

So not only is Super Bowl 2008 going to be a rematch between the Giants and Patriots, it is also going to be a rematch with the same head referee -- Mike Carey. In the Giants-Patriots game in week 17, there were 5 penalties accepted for 42 yards against the Patriots and there were 5 penalties accepted for 53 yards against the Giants.

Check back later for more analysis of Mike Carey and -- we hope -- the others in the Super Bowl referee crew. Post comments if you have questions, ideas, or if you find out the other members of the Super Bowl crew.

Giants Do Not Typically Win Through High-Yardage Penalties

2008-01-19T07:26:00.000-05:00

In the footballoutsiders preview of the Giants-Packers game (www.footballoutsiders.com), they predict that the Giants offense might get some free yardage because the Packers' secondary led the NFL in pass interference and illegal contact penalties, which gave 34 yards per game to the opposing offense. (I am not tracking those types of statistics, so I can't say whether that's correct.)

This led me to take a look at this season's statistics for the Packers and Giants to take a quick look at whether the teams' results depended to some degree on a large number of penalties or a large number of yards per penalty. A large number of penalties suggests the referee crew that game called lots of penalties, perhaps lots of defensive penalties as part of the mix. A large number of yards per penalty might be a sign of calling defensive pass interference (which can be a large number of yards), but might be a sign of other large-yardage penalties. Not a perfect way to analyze this, but the best I can do.

Looking at the 2007 regular season, the Giants did not typically win in games where there was a large penalty yards per penalty called. If we look at the Giants' games with the largest actual yards per penalty, the Giants went only 3-5. Meanwhile, in the eight games with the smallest actual yards per penalty, the Giants went 7-1.

Looking at the expected yards per penalty (using the referee's season-long statistic as opposed to the actual figure in the game) does not yield any trend -- the Giants went 5-3 in the eight largest and 5-3 in the eight smallest games. So it seems like the trend depends on the actual yards per penalty called in the particular game and is unrelated to the referees' season-long trends. You get equal 5-3 splits when you look at the actual number of penalties called per game and when you look at the expected penalties per game using the referees' regular season statistics.

Turning to the Packers: actual yards per penalty, 7-1 for largest 8 and 6-2 in smallest 8. expected yards per penalty, 6-2 in largest 8 and 7-1 in smallest 8. For actual penalties per game, 6-2 for largest 8 and 7-1 in smallest 8. For expected penalties per game, 7-1 in largest 8 and 6-2 in smallest 8. So for the Packers, no obvious trends.

So if past performance holds up on Sunday, the Giants typically do best when the average yards per penalty is less than 8 -- and is not typically characterized by a bunch of large yardage defense pass interference calls. Still, the Giants didn't lose all their games with large yards per penalty -- they did go 3-5 so it's not impossible, just not their typical type of win.

Post-game update: the initial box score of the Giants OT victory over the Packers says there were 6 penalties for 50 yards against the Giants and 7 penalties for 37 yards against the Packers, for an average yards per penalty of 6.69 yards per penalty. It was below 8 yards per penalty on average, which was typical of the Giants' victories this season. Of course, the Giants only barely won and the average yards per penalty is not exactly a statistic many people focus on so this probably was just a statistical oddity as opposed to anything deep...

NFL Conference Championships (i.e. the semifinals): Chargers at Patriots and Giants at Packers

2008-01-16T20:09:00.001-05:00

Various bloggers are listing the likely referees for the upcoming NFL Conference Championships in the San Diego Chargers at New England Patriots game and the New York Giants at the Green Bay Packers.

As in other playoffs, the NFL is mixing up the crews. Let's take a look at the crews for each game. In parentheses is the crew that the official was part of during the regular season:

Chargers at Patriots:
R- Jeff Triplette (Triplette)
U- Butch Hannah (Anderson)
HL- Steve Stelljes (Triplette)
LJ- Gary Arthur (Carollo)
FJ- Tom Sifferman (Hochuli)
SJ- Greg Meyer (Triplette)
BJ- Greg Steed (Triplette)

So the Chargers game is pretty much a Triplette crew with just a few substitutes. Can we analyze it as if it will be similar to the usual Triplette crew or will the substitutes mess up our ability to predict how this crew will perform?

Giants at Packers:
R- Terry McAulay (McAulay)
U- Roy Ellison (Winter)
HL- Jim Mello (McAulay)
LJ- Jeff Bergman (Boger)
FJ- Scott Steenson (Boger)
SJ- Rick Patterson (Anderson)
BJ- Perry Paganelli (Parry)

Wow, only the head linesman is from McAulay's crew. This is really a mixture of lots of different crews -- the seven officials come from five different crews. We can analyze the regular season numbers of McAulay's regular season crew, but this bunch might really be different from how McAulay's crew did in the regular season. As if trying to predict the tendencies of referee crews weren't hard enough, now we have to factor in the mixture of the crews.

Let's look at the regular season statistics for the crews led by the same referee:

Chargers at Patriots: Jeff Triplette. Tied for 5th out of 17 for best ref for the home team's winning rate (67%). Near the bottom in penalties per game (14th) and yards per penalty (15th) so of course near the bottom in penalty yards per game (15th). 4th-most for percent of penalties called against the visiting team (55%). Middle of the pack (9th) in total points scored per game and near the top (4th) in home team points scored per game. Near the bottom (16th) in amount of penalty yards called against the home team at just 36.8 per game. Tied at the top in the percent of his games in which the visiting team had more penalties than the home team (70%). Overall, home teams did pretty well in Jeff's games during the regular season with not so many penalties called per game -- especially few called against the home team. Note: see a separate blog post for 2008 statistics. These are the 2007 statistics.

Giants at Packers: Terry McAulay. (Well, Terry has a mixed crew but let's look at this as if it were Terry's regular season crew so we can draw on our statistics. Why look at the real crew when the only stats we have are for the regular season crew, right?) Tops for the home team winning rate at 75%. This guy was great for home teams in the regular season! Strangely, the lowest total points scored per game of any of the refs at 35.5 per game. Second-lowest for visiting team points per game (15.9) and worst for home team points per game (19.6). For penalties, middle of the pack on number per game and a bit on the high side for average yards per penalty. Number one in calling the largest percentage of penalties and penalty yards against visiting teams (59% by penalties and 60% by penalty yards)! On average 18.9 more penalty yards against visiting teams per game than against home teams.

Let's look at the Giants-Packers crew for home team win rate, knowing it's a mixed crew. The referee and heads linesman were on the top crew for home teams in the regular season. The line judge, field judge, and back judge were on crews that tied for second-best for home teams. The side judge was on the 9th best out of 17 for home teams. Only the umpire worked on a pro-visiting team crew, which was 15th out of 17 for home team win rate in the regular season.

Overall, if you assume the referees control everything and that the players on the field had nothing to do with the results of any of the games (have I made it clear that this whole analysis requires a huge disclaimer?), then I'd say that the crew on the Giants-Packers game would be a very good one for the home team (Packers) and that the crew in the Chargers-Patriots game is pretty good for the home team (Patriots). If the Chargers fall behind early, I might suggest that they start committing penalties and hope that Jeff Triplette (somewhat near the bottom in penalties per game) lets both teams get away with a little holding here and there.

It's like knowing the strike zone for the particular umpire in baseball -- if the referee has certain tendencies, you should use that knowledge to your advantage during the game! Just make sure you aren't videotaping the other team's sideline. Or go ahead if it'll help you win, just pay a little money afterwards.

NFL Quarterfinals: New York Giants-Dallas Cowboys and Pete Morelli

2008-01-13T13:49:00.000-05:00

According to the blog hw's World of Sports (http://journals.aol.com/dothechop71029/ListenUp/), the playoff game between the New York Giants and Dallas Cowboys today (January 13, 2008) in the NFL playoffs will be covered by referee Pete Morelli using the John Parry's crew.

If that's correct, then it's hard to know whether to apply the regular season statistics for Pete Morelli (today's referee) or for John Parry (the officials other than the referee)! Let's take a quick look at both, but focus on Pete Morelli because he is just so much more interesting!

Pete Morelli: second-least penalties per game (9.7), second-least in penalty yards per game (77), 16th of 17 in percent of penalty yards against the visiting team (50%), 16th in difference in visitor penalty yards greater than home penalty yards (0.1), 2nd in total points (47.7), 2nd in visitor points (25), 15th in visitor penalty yards per game (38.6), last in home penalties per game (4.4), last in home win rate (33%).

John Parry: 7th in penalties per game, 3rd in penalty yards per game (100), 4th in yards per penalty, 2nd in percent of penalty yards against the visiting team (58%), 2nd in difference in visitor penalty yards greater than home penalty yards (15.7), 7th in total points (43.8), tied for second with two others in home win rate (73%).

What to me is the most interesting about Pete Morelli is that he had by far the worst win rate for the home team in his games this season. Home teams only won 33% of the games he handled. The two next-lowest refs were up at 40%. Home teams lost seven games in a row in Pete's games (weeks 3-11) and then three in a row (weeks 14-16). The losing home teams were Houston, Carolina, Buffalo, Miami, Chicago, Oakland, Baltimore, San Francisco, Giants, and New Orleans. Very interesting. But it could be interesting because the NFL might pair up Pete Morelli with John Parry's crew and home teams did very well in John's games this year. Will this mix and mash effort somehow attempt to even off the skewed regular season statistics?

There are several areas where Pete Morelli and John Parry were on different extremes during the regular season. Pete was near the top of all of the following categories while John was near the bottom: fewest penalty yards per game, percent of penalty yards called against the home team, and penalty yardage differential called against the home team.

Only in the playoffs would a referee be torn away from his usual crew and transplanted with a new crew. So there are few examples to help us draw a conclusion about what might happen in the Giants-Cowboys game later today.

So, for the Giants fans, keep rooting for the Morelli Curse to strike the Cowboys as today's home team! And Cowboys fan should root like crazy that the Morelli Curse was actually embodied by Pete's crew and not Pete himself so that the Cowboys can escape the curse.

Maybe the location of the Morelli Curse will have more of an impact on today's game than the location of Jessica Simpson?

Jaguars-Patriots NFL Playoffs: Referee Jerome Boger

2008-01-12T22:15:00.000-05:00

THe Jacksonville Jaguars visit the New England Patriots tonight in the NFL playoffs and it looks like Jerome Boger is the referee. Let's take a quick look at Jerome's statistics during the season.

Remember, playoff referee crews are all mixed up from various groups that did not work together during the year. Jerome's statistics were racked up with a specific set of referees he worked with all season. So the regular season statistics might not be so important in the playoffs. Enough of these explanations already --

Jerome Boger had the fourth-most accepted penalties per game out of the 17 crews this year at 12.5 (average was around 11.5). Middle of the pack on total penalty yards. Somewhat near the bottom in average yards per penalty at 7.6 (13th out of 17).

Third-most percent penalties called against the visiting teams at 56%. Also third-most in percent of the penalty yards being called against the visiting teams at 56% too. Not a surprise second-most in the raw difference in penalties (1.4) called on the visiting teams and 4th-most in raw different in penalty yards (10.8) called on the visiting team.

His games were pretty low-scoring, ranking second-lowest at 37.7 total points per game with the lowest visiting team scoring per game at 15.7 points per game.

Home teams did well in Jerome's games this year -- winning 73% of the games, tying him for second-best for home teams with two other referees. That certainly would be a great sign for the Patriots if only you ignored reality that the quality of the teams probably has a great deal more to do with the odds a team will win than whether a referee might have a tendency to have the home team win more often!

Post your comments on the refereeing in the game and any questions on Jerome's referee statistics as a comment to this posting.

Jacksonville Jaguars and Pittsburgh Steelers Wild Card Game: Scott Green

2008-01-05T20:30:00.000-05:00

Let's take a quick look at the wild card playoff game between the Jacksonville Jaguars and the Pittsburgh Steelers. The referee is Scott Green. Let's take a look at Scott Green in the 2007 NFL season.

But first, keep in mind that he is not working with his usual crew -- so statistics about his crew in the regular season don't seem to be as valid for the playoffs unless you imagine that the ref sets the tone for the rest of the crew.

And of course keep in mind that we are looking at statistics that only make sense if they to some degree depend on variations among the different ref crews.

Back to looking at Scott Green:
Home teams won 53% of the time (middle of the pack)
Total penalties were 10.7 per game, a little below average
Average yards per penalty was 8.6, which was second-highest and quite above average.
Total points per game was 45.5, which was fourth-highest so maybe it could be higher scoring than you'd ordinarily expect.
By the way, visiting teams averaged 24.1 points and home teams averaged 21.5 points.

Post comments if you have questions or comments on the game!

NFL Teams 2007 compared with referees in their games

2008-01-05T10:11:00.001-05:00

What if we pretend that the main "opponent" that a team faces in a game is the referee and whether that referee tends to favor the home or visiting team?

In that imaginary situation, we can check whether a particular team had a ref that favored visiting teams when it was the visiting team and whether it had a ref that favored the home teams in its home games.

We can then add it up across the season and see which teams had the easiest or hardest referee schedule (assuming that referees consistently tend to favor either the home or visiting teams) and we can see how much better each team did against the projected wins!

Let's start with the teams with the easiest and hardest "referee schedule":

Easiest schedules:
Seattle: 9.21 projected wins, 10 actual wins
Indianapolis: 9.17 projected wins, 13 actual wins
Tennessee: 8.89 projected, 10 actual
Minnesota: 8.72 projected, 8 actual
Detroit: 8.72 projected, 7 actual
Dallas: 8.60 projected, 13 actual

Hardest schedules:
St Louis: 6.64 projected, 3 actual
Chicago: 7.04 projected, 7 actual
Atlanta: 7.15 projected, 4 actual
New Orleans: 7.30 projected, 7 actual
San Diego: 7.33 projected, 11 actual (wow, San Diego had a hard schedule yet still made the playoffs)

Here's the list of the teams that did the best over the projected wins, relying only on the referee schedule (which of course is an artifical scenario):
New England: 7.82 (16-8.18)
Green Bay: 5.02 (13-7.98)
Dallas: 4.40 (13-8.60)
Indianapolis: 3.83 (13-9.17)
San Diego: 3.67 (11-7.33)
Jacksonville: 3.20 (11-7.80)
Cleveland: 1.89 (10-8.11)
New York Giants: 1.87 (10-8.13)

at the bottom:
Miami: -6.65 (1-7.65)
Kansas City: -4.01 (4-8.01)
Oakland: -3.85 (4-7.85)
St Louis: -3.64 (3-6.64)
New York Jets: -3.42 (4-7.42)
Atlanta: -3.15 (4-7.15)

Let's use these limited statistics to check out Washington at Seattle in the wild card game:
Washington: 0.46 adjusted wins (9-8.54) versus Seattle: 0.79 adjusted wins (10-9.21)
If perhaps Walt Coleman is the referee (47% home win rate), then you tack in the adjusted wins, that would mean Seattle would have a 49% chance of winning, ignoring such critical factors as how good their players are and how tough their opponents are.

Clearly, there are tons of limitations to this analysis!

NFL Referee Tendencies Across the 2006-2007 Seasons

2008-01-05T09:39:00.000-05:00

Let's look at correlations between the distribution of statistics among the 2006 NFL referees and the 2007 NFL referees. This is a rough attempt at figuring out which particular characteristics seem to hold the following season. For example, if referees A, B, C, and D called lots of penalties in 2006 and referees E and F didn't, let's see whether the same kind of distribution exists in 2007 -- whether A, B, C, and D called lots of penalties and E and F didn't in 2007 too.

Running the numbers and checking for a correlation, some seem to hold up across the 2006 and 2007 seasons. In order of the correlation coefficient:
Average yards per penalty (0.595)
Penalties against home teams (0.489)
Penalty yards against home teams (0.417)
Total penalty yards (0.394)
Total penalties (0.392)
Penalty yards against visiting teams (0.332)
Percent penalty yards against visiting team (0.240)
Difference in yards against visiting teams (0.236)

Let's look at those with the worst correlation coefficients across two seasons:
Home team win rate (-0.172)
Points scored by home teams (-0.163)
Difference in number of penalties against visiting teams (-0.146)
Percent of penalties called against visiting teams (-0.120)

NFL 2007 Referee Statistics (including all regular season games)

2008-01-05T09:21:00.000-05:00

Here are the final NFL referee statistics for the 2007 regular season, including all regular season games:

Possible relationship between the number of penalties called and the rate the home team wins for a particular referee. The strong correlation between the number of penalties per game and the rate the home team wins as usual came out with a positive correlation -- it decreased a bit toward the end of the year but ended up with 0.216.

Referees by penalties accepted per game (followed by home win rate):
Ron had a huge lead and kept the top spot to be the 2007 leader in penalties per game. Notice many of the referees who call lots of penalties also have a high win rate for home teams.
Ron Winter (14.3, 40%)
Tony Corrente (13.3, 73%)
Walt Anderson (12.7, 60%)
Jerome Boger (12.5, 73%)

and at the bottom, Gerald locked up the title and kept it to the end:
Jeff Triplette (10.6, 67%)
Bill Carollo (9.8, 63%)
Pete Morelli (9.7, 33%)
Gerald Austin (8.9, 50%)

Referees by home win-rate: if you believe the referee has some influence (perhaps an unintentional tendency) on whether the home team wins, then use this list. Here's the list, again with the penalties per game followed by the home team's win-rate. Terry McAulay kept his lead and home teams did the best in games where Terry was the referee:
Terry McAulay (12.1, 75%)
Tony Corrente (13.3, 73%)
Jerome Boger (12.5, 73%)
John Parry (12.1, 73%)

And at the bottom, Green Bay broke through the Peter Morelli curse by winning as a home team one of his games. The home teams went 5-10 in Peter's games this year, winning the first two, losing the next seven, winning two, losing three, and winning the last one.
Bill Leavy (12.1, 45%)
Ron Winter (14.3, 40%)
Mike Carey (11.8, 40%)
Pete Morelli (9.7, 33%)

So, if you like the home team, hope for Terry McAulay, Tony Corrente, Jerome Boger, and John Parry. If you like the visiting team, hope for Pete Morelli but also good are Bill Leavy, Ron Winter, and Mike Carey. Of course, this is only if you think particular referee crews are better for home teams than others.

And here is some end-of-year extra data for you -- in order are the following statistics for each referee -- penalties accepted per game, penalty yards per game, average yards per penalty, percent penalties called against visiting team, total points scored, visiting team points, home team points, home team win rate. Post a comment if you request other types of data or want any particular theory investigated or calculations run!
Anderson, Walt (12.7, 97, 7.6, 50%, 41.7, 20.3, 21.3, 60%)
Austin, Gerald (8.9, 80, 9.0, 50%, 45.4, 19.8, 25.6, 50%)
Boger, Jerome (12.5, 95, 7.6, 56%, 37.7, 15.7, 22.1, 73%)
Carey, Mike (11.8, 90, 7.6, 54%, 45.0, 23.5, 21.5, 40%)
Carollo, Bill (9.8, 72, 7.4, 54%, 40.2, 17.8, 22.4, 63%)
Coleman, Walt (10.7, 81, 7.6, 51%, 43.3, 22.3, 21.1, 47%)
Corrente, Tony (13.3, 105, 7.9, 53%, 43.1, 18.5, 24.5, 73%)
Green, Scott (10.7, 92, 8.6, 53%, 45.5, 24.1, 21.5, 53%)
Hochuli, Ed (12.4, 95, 7.7, 53%, 46.1, 19.9, 26.3, 63%)
Leavy, Bill (12.1, 94, 7.7, 56%, 41.5, 21.0, 20.5, 45%)
McAulay, Terry (12.1, 97, 8.1, 59%, 35.5, 15.9, 19.6, 75%)
Morelli, Pete (9.7, 77, 7.9, 55%, 47.7, 25.0, 22.7, 33%)
Nemmers, Larry (10.8, 90, 8.4, 51%, 43.7, 17.3, 26.4, 67%)
Parry, John (12.1, 100, 8.3, 51%, 43.8, 18.7, 25.1, 73%)
Steratore, Gene (10.7, 82, 7.6, 48%, 50.6, 25.3, 25.3, 50%)
Triplette, Jeff (10.6, 79, 7.4, 55%, 43.5, 18.2, 25.3, 67%)
Winter, Ron (14.3, 106, 7.4, 53%, 42.5, 21.3, 21.1, 40%)

Patriots-Giants Week 17: Mike Carey Is The Referee

2007-12-29T20:20:00.000-05:00

For the December 29, 2007 week 17 game between the Patriots and Giants, the referee crew is headed by Mike Carey. Let's take a look at his crew's statistics for the 2007 NFL season:

His games have slightly more points scored than you would expect for the teams involved (43.0 rather than 43.3) and the visiting teams have scored more points than the home teams, but in general the visiting teams in his games were stronger this season.

Visiting teams: scored 22.5 points where 22.5 points expected (4th highest among refs)
Home teams: scored 20.9 points where 20.5 points expected (3d lowest among refs)

Let's look at other categories:
Penalties per game (11.9 or middle of the pack), penalty yards per game (89, slightly less than average), average penalty yards per penalty (7.5, near the lowest of the refs so don't expect a large number of big-yardage pass interference calls).

For the home team's win rate, it is only at 43%, which ties Mike Carey for third-worst for home teams among the 17 referees. I guess this is a good sign for the Patriots if you believe some referees are better for home teams than others.

Looking at the season, he refereed the Patriots 48-27 win as visitors over the Cowboys in week 6. He has not done a Giants game this year. So, advantage Patriots.

In the 2006 season, by the way, he handled the Giants 42-30 loss while visiting the Seahawks in week 3. And the Patriots 35-0 victory while visiting the Packers in week 11. So maybe the Patriots have a slight advantage there, too?

Post a comment if you have any specific questions about Mike Carey...

Over/Under NFL Referee Rankings (after 2007 Week 16)

2007-12-25T09:39:00.001-05:00

Here we analyze the total number of points scored (over/under) for each referee crew this season. Let's compare it to two items -- first, compare referees by the average total points scored in games they covered. Second, adjusted total points by comparing the average total points to what you would expect for the teams involved (using their average points per game season-long).

There is little change between the rankings of total points and adjusted total points at the top:
Gene Steratore (+7.0, 50.4)
Pete Morelli (+3.9, 47.7)
Scott Green (+3.6, 46.4)
Larry Nemmers (+2.7, 45.2)

The bottom is affected by using adjusted total points as opposed to total points -- Bill Leavy falls back (from third-lowest in total points to sixth-lowest in adjusted total points):
Terry McAulay (-8.3, 34.7)
Jerome Boger (-6.5, 37.5)
Walt Coleman (-2.1, 41.9)
Tony Corrente (-2.0, 41.1)
Bill Carollo (-1.3, 41.1)
Bill Leavy (-1.3, 39.8)

Bill Leavy had an unusually low expected total points this season after 16 weeks. At 41.1 total points expected, that was much lower than the next-lowest of 42.4 for Bill Carollo.

We also see an interesting correlation -- referees with large total points scored (or large adjusted total points) are in general worse for home teams! The correlation between total points per ref and home win-rate per ref is -0.535 and the correlation between adjusted total points and home win-rate is -0.540.

For example, Pete Morelli is the best for visiting teams through week 16 (home teams only win 29% of the games) and Pete also has a large total points per game (second largest at 47.7 per game). At the bottom, Terry McAulay is great for home teams (home teams win 80% of the games so far) and Terry has the lowest total points per game (lowest at 34.7 per game).

So, in general, if a referee tends to have low-scoring games, it's better for the home teams this season. What is the hypothesis there? We separately looked at how those who call more penalties tend to have home teams win more often.

Maybe the hypothesis is: if referees call penalties, there might be an unconscious bias to help out the home team such as perhaps from crowd pressure. And the way referees will affect the game with more penalties is to reduce the total number of points scored. So perhaps under this theory, less penalties means better for visiting teams and as a byproduct, more total points per game. On the other hand, more penalties means better for home teams and as a byproduct of the penalties, less total points per game. Post your comments to this speculative theory!

NFL Referee Statistics (after week 16, games of December 24, 2007)

2007-12-25T08:30:00.000-05:00

Here are the updated NFL referee statistics after week 16 (including games through December 24, 2007):

Possible relationship between the number of penalties called and the rate the home team wins for a particular referee. The strong correlation between the number of penalties per game and the rate the home team wins actually decreased a bit after dropping for two weeks. It dipped slightly from 0.247 to 0.234.

Referees by penalties accepted per game (followed by home win rate):
Ron's huge lead whittles away by a little bit but he seems assured of winning the title this season:
Ron Winter (14.6, 43%)
Tony Corrente (13.4, 71%)
Walt Anderson (12.9, 57%)
Jerome Boger (12.7, 71%)

and at the bottom, Gerald has the title pretty much locked up too:
Jeff Triplette (10.3, 64%)
Pete Morelli (9.8, 29%)
Bill Carollo (9.6, 60%)
Gerald Austin (8.7, 47%)

Referees by home win-rate: if you believe the referee has some influence (perhaps an unintentional tendency) on whether the home team wins, then use this list. Here's the list, again with the penalties per game followed by the home team's win-rate. Terry McAulay keeps his comfortable lead with yet another home-team victory:
Terry McAulay (11.9, 80%)
John Parry (12.1, 73%)
Tony Corrente (13.4, 71%)
Jerome Boger (12.7, 71%)

And at the bottom, a visiting team has yet again won in one of Peter Morelli's games. The New Orleans Saints are this week's team to run into the Morelli Curse. From the viewpoint of the home team in Peter Morelli's games, the season has gone WWLLLLLLLWWLLL (two wins, seven losses, two wins, and three losses so 4-10). Pete Morelli has the worst win-rate for home teams this season.
Ron Winter (14.6, 43%)
Mike Carey (11.9, 43%)
Bill Leavy (12.0, 40%)
Pete Morelli (9.8, 29%)

So, if you like the home team, hope for Terry McAulay, John Parry, Tony Corrente, or John Boger. If you like the visiting team, hope for Pete Morelli but also good are Bill Leavy, Mike Carey, and Ron Winter. Of course, this is only if you think particular referee crews are better for home teams than others.

Here is the information, alphabetically, with total penalties, total yards, and home win-rate:
Walt Anderson (12.9, 99, 57%)
Gerald Austin (8.7, 77, 47%)
Jerome Boger (12.7, 97, 71%)
Mike Carey (11.9, 89, 43%)
Bill Carollo (9.6, 70, 60%)
Walt Coleman (10.9, 82, 50%)
Tony Corrente (13.4, 108, 71%)
Scott Green (10.8, 93, 50%)
Ed Hochuli (12.3, 93, 60%)
Bill Leavy (12.0, 92, 40%)
Terry McAulay (11.9, 95, 80%)
Pete Morelli (9.8, 77, 29%)
Larry Nemmers (10.6, 89, 64%)
John Parry (12.1, 100, 73%)
Gene Steratore (10.9, 84, 53%)
Jeff Triplette (10.3, 76, 64%)
Ron Winter (14.6, 106, 43%)

NFL Referees and Points Per Game

2007-12-22T08:42:00.000-05:00

Let's take a look at points per game by referee in the 2007 NFL season so far. Do you think this statistic has any correlation to the rate that the home team wins? Do you think it matters which referee you have?

We can't yet answer the second question, but as far as the first one -- yes, there is a correlation between the total number of points per game and the rate the home team wins. In general, if you have a referee who usually has low scoring games, the referee will usually have home teams win more often.

There is an 0.425 correlation for that. (The correlation to the points scored by the visiting team is an obvious -0.716 because of course if thevisiting team scores less, the home team wins more often. For the points scored by the home team, the correlation is only a mild 0.206)

Here is the breakdown, with the following statistics: referee, total points per game, average visiting team points, and average home team points). This is through week 15 of the 2007 NFL season:

Steratore, Gene (48.2, 22.4, 25.8)
Green, Scott (45.6, 25.2, 20.4)
Morelli, Pete (44.9, 23.1, 21.8)
Austin, Gerald (44.7, 18.8, 25.9)
Nemmers, Larry (44.0, 16.7, 27.4)
Parry, John (43.8, 18.5, 25.3)
Winter, Ron (42.7, 21.2, 21.5)
Carey, Mike (42.2, 21.1, 21.1)
Hochuli, Ed (41.7, 17.5, 24.1)
Triplette, Jeff (40.6, 17.7, 22.8)
Carollo, Bill (40.4, 18.2, 22.2)
Coleman, Walt (40.2, 19.8, 20.5)
Corrente, Tony (40.0, 16.6, 23.5)
Anderson, Walt (39.7, 18.3, 21.5)
Leavy, Bill (36.4, 17.4, 19.0)
McAulay, Terry (35.1, 14.7, 20.4)
Boger, Jerome (34.7, 14.7, 20.0)

Finding Referee Trends That Hold Up Across Seasons

2007-12-22T08:25:00.000-05:00

NFL referees have a variation among them for each statistical category. Can we look at the variations to see whether any of the variations appear not only in the 2006 season but also the 2007 season? If we can find a variation that holds up across two seasons, it suggests that the characteristic is something that depends on the particular referee and is not just by chance.

One way to try to look into this is to see if there is a correlation between a particular referee's 2006 statistic and his 2007 statistic in the same category. For example, if you chart out each referee's average number of penalties per game in 2006 and then compare it ref-by-ref to each referee's numbers for 2007, you can find out the correlation if you plotted them on a graph.

Let's look for correlations across the 2006 and 2007 seasons in a variety of categories:

Strong correlations (suggesting this does depend on the referee) -- comparing the full 2006 season to the 2007 season through week 15 for the referees who worked in both 2006 and 2007:
Average yards per penalty (0.544)
Number of penalties for the home team (0.407)
Total penalty yards (0.378)
Number of penalties (0.364)
Yards per penalty for the home team (0.364)
Yards per penalty for the visiting team (0.361)
% of games where the visiting team had more penalties called (0.332)

Weak correlations (suggesting this does not depend on the referee):
Difference in number of penalties for the visiting and home teams (-0.170)
Percent of penalties called on the visiting team (-0.158)
Home team win percentage (-0.039)

Please post your thoughts on whether you think this attempt to find correlations across seasons is some indicator of whether a characteristic may depend on the particular referee!

NFL Ref Statistics (through week 15, after games of December 17, 2007)

2007-12-22T08:04:00.000-05:00

Here are the updated NFL referee statistics after week 15 (including games through December 17, 2007):

Possible relationship between the number of penalties called and the rate the home team wins for a particular referee. The strong correlation between the number of penalties per game and the rate the home team wins actually decreased a bit after dropping for two weeks. It slumped again from 0.247 to 0.227. Refs who generally call more penalties are more likely to have the home team win.

I'm doing extended analysis in looking for correlations between the 2006 referee statistics and the 2007 referee statistics to see if some trends hold up across seasons according to the particular referee...

Referees by penalties accepted per game (followed by home win rate):
Ron extends his 0.9 lead up to 1.7 and pretty much has the season title locked:
Ron Winter (15.2, 38%)
Walt Anderson (13.5, 62%)
Tony Corrente (13.2, 69%)
Jerome Boger (12.4, 69%)

and at the bottom no changes:
Scott Green (10.5, 46%)
Bill Carollo (9.9, 57%)
Pete Morelli (9.8, 31%)
Gerald Austin (8.8, 43%)

Referees by home win-rate: if you believe the referee has some influence (perhaps an unintentional tendency) on whether the home team wins, then use this list. Here's the list, again with the penalties per game followed by the home team's win-rate. Terry McAulay keeps his comfortable lead with yet another home-team victory:
Terry McAulay (12.1, 79%)
John Parry (12.2, 71%)
Tony Corrente (13.2, 69%)
Jerome Boger (12.4, 69%)

And at the bottom, a visiting team has yet again won in one of Peter Morelli's games. The New York Giants are this week's team to run into the Morelli Curse. From the viewpoint of the home team in Peter Morelli's games, the season has gone WWLLLLLLLWWLL (two wins, seven losses, two wins, and two losses so 4-9). Pete Morelli (who had the worst win-rate for home teams in 2006 for the refs also working in 2007) still has the worst win-rate for home teams.
Bill Leavy (11.9, 44%)
Gerald Austin (8.8, 43%)
Ron Winter (15.2, 38%)
Pete Morelli (9.8, 31%)

So, if you like the home team, hope for Terry McAulay, John Parry, Tony Corrente, or John Boger. If you like the visiting team, hope for Pete Morelli but also good are Ron Winter, Gerlad Austin, Bill Leavy. Of course, this is only if you think particular referee crews are better for home teams than others.

Here is the information, alphabetically, with total penalties, total yards, and home win-rate:
Anderson, Walt (13.5, 102, 62%)
Austin, Gerald (8.8, 78, 43%)
Boger, Jerome (12.4, 94, 69%)
Carey, Mike (12.2, 92, 46%)
Carollo, Bill (9.9, 70, 57%)
Coleman, Walt (10.9, 83, 46%)
Corrente, Tony (13.2, 107, 69%)
Green, Scott (10.5, 90, 46%)
Hochuli, Ed (12.4, 93, 57%)
Leavy, Bill (11.9, 92, 44%)
McAulay, Terry (12.1, 96, 79%)
Morelli, Pete (9.8, 76, 31%)
Nemmers, Larry (10.6, 89, 64%)
Parry, John (12.2, 101, 71%)
Steratore, Gene (10.9, 85, 57%)
Triplette, Jeff (10.5, 79, 62%)
Winter, Ron (15.2, 111, 38%)

NFL Referee Statistics (through week 14, December 10, 2007)

2007-12-15T09:34:00.000-05:00

Here are the updated NFL referee statistics after week 14 (including games through December 10, 2007):

Possible relationship between the number of penalties called and the rate the home team wins for a particular referee. The strong correlation between the number of penalties per game and the rate the home team wins actually decreased a bit after week 13's huge drop. It slumped from 0.278 to 0.247. Refs who generally call more penalties are more likely to have the home team win.

Possible relationship between the referee who calls the game and how many penalties there are and the rate the home team wins the game. One way to check on whether the referee has a relationship to how many penalties are called or the rate the home team wins is to compare those statistics in 2007 with the same statistics for those referees in 2006. Then to see if there is some correlation between the 2006 rates and the 2007 rates for those referees. A comparison of those referees with stats in 2006 and the 2007 season so far suggests there is a relation between the ref and penalties called or home team win-rate. The correlation for penalties called is pretty strong at 0.316 (up from 0.269) while the correlation for the home team's win rate jumped back up after last week's drop and is a strong 0.393 (up from 0.249)

Referees by penalties accepted per game (followed by home win rate):
Ron slightly extends his lead over Walt:
Ron Winter (14.9, 42%)
Walt Anderson (14.0, 58%)
Tony Corrente (13.1, 67%)
Terry McAulay (12.8, 77%)

and at the bottom no changes:
Scott Green (10.5, 46%)
Bill Carollo (10.0, 54%)
Pete Morelli (10.0, 33%)
Gerald Austin (8.8, 46%)

Referees by home win-rate: if you believe the referee has some influence (perhaps an unintentional tendency) on whether the home team wins, then use this list. Here's the list, again with the penalties per game followed by the home team's win-rate. Terry McAulay keeps his comfortable lead with another home-team victory:
Terry McAulay (12.8, 77%)
John Parry (12.8, 69%)
Larry Nemmers (10.7, 69%)
with Tony Corrente and Jerome Boger tied at 67%

And at the bottom, a visiting team once again won in one of Peter Morelli's games. From the viewpoint of the home team in Peter Morelli's games, the season has gone WWLLLLLLLWWL (two wins, seven losses, two wins, and one more loss so 4-8). Pete Morelli (who had the worst win-rate for home teams in 2006 for the refs also working in 2007) still has the worst win-rate for home teams.
Ron Winter (14.9, 42%)
Mike Carey (12.3, 42%)
Walt Coleman (11.5, 42%)
Pete Morelli (10.0, 33%)

So, if you like the home team, hope for Terry McAulay, John Parry, Gene Steratore, or Larry Nemmers. If you like the visiting team, hope for Pete Morelli but also good are Ron Winter, Mike Carey, and Walt Coleman. Of course, this is only if you think particular referee crews are better for home teams than others.

Here is the information, alphabetically, with total penalties, total yards, and home win-rate:
Anderson, Walt (14.0, 105, 58%)
Austin, Gerald (8.8, 78, 46%)
Boger, Jerome (12.4, 94, 67%)
Carey, Mike (12.3, 94, 42%)
Carollo, Bill (10.0, 72, 54%)
Coleman, Walt (11.5, 87, 42%)
Corrente, Tony (13.1, 105, 67%)
Green, Scott (10.5, 90, 46%)
Hochuli, Ed (12.3, 93, 54%)
Leavy, Bill (11.8, 92, 50%)
McAulay, Terry (12.8, 102, 77%)
Morelli, Pete (10.0, 76, 33%)
Nemmers, Larry (10.7, 90, 69%)
Parry, John (12.8, 107, 69%)
Steratore, Gene (11.4, 88, 62%)
Triplette, Jeff (10.6, 78, 58%)
Winter, Ron (14.9, 109, 42%)

NFL Fines Three Baltimore Ravens for Criticizing Officials

2007-12-08T10:00:00.000-05:00

The NFL fined Samari Rolle, Chris McAlister, and Derrick Mason $15,000 each for publicly questioning the integrity of the officiating in the game between the New England Patriots and the Baltimore Ravens.

Coach Brian Billick went even further in gagging NFL players and any commentary about how well the referees performed -- he talked a number of times to his team "about not speaking publicly about any unhappiness we have with the officials."

If the NFL, NFL coaches, and NFL players have a gag rule to prevent them from saying anything about NFL referees, then it is up to the fans and sports writers to comment on the referees!

Referees are human beings and just like players, sometimes they have good days and sometimes they unintentionally have a bad game. That's not cheating, that's just being a human being and doing better some games than others. Why aren't sports writers and journalists commenting on the referees and how they are doing? Right now, many sports writers depend on the coaches and players to give quotes and lead what they will mirror in their stories. But it's clear the NFL is gagging everyone from saying a single word about the referees, so it's up to the writers to take some initiative and comment on them without prompting from the players or coaches.

People who didn't have a chance to watch the game would like to see some opinionated, fair explanation of what happened. If someone makes a sensational catch, the article should say it was a spectacular catch and not just report the bland fact of "completion for 25 yards." Same for if a player makes a terrible play, tell us the player dropped an easy catch as opposed to a very bland statement of "pass attempted fell incomplete" with no explanation. And the same for the referees -- if a referee makes an obviously bad call, tell us what happened and say it was a bad call as opposed to saying nothing at all.

I am not saying that writers should speculate about whether referees are trying to cheat. When it comes to the players, if someone drops an easy catch, writers should not be saying that the player was cheating and trying to lose. Same for referees -- you can say that a referee made a bad call without suggesting that the referee is actually cheating and trying to make either team lose.

If the NFL is gagging players from giving quotes on what actually happened on the field, it's up to the writers to earn their money and actually write about what they saw. Otherwise, fire them and get better writers...

NFL Referee Statistics (after week 13, through December 3, 2007)

2007-12-08T09:15:00.000-05:00

Here are the updated NFL referee statistics after week 13 (including games through December 3, 2007):

Week 13 was unusual for a few reasons -- many referees went somewhat against the trend for home team wins and penalties called for the season. Let's take a look:

Possible relationship between the number of penalties called and the rate the home team wins for a particular referee. The strong correlation between the number of penalties per game and the rate the home team wins dropped by quite a bit from 0.449 down to 0.278! Refs who generally call more penalties are more likely to have the home team win.

Possible relationship between the referee who calls the game and how many penalties there are and the rate the home team wins the game. One way to check on whether the referee has a relationship to how many penalties are called or the rate the home team wins is to compare those statistics in 2007 with the same statistics for those referees in 2006. Then to see if there is some correlation between the 2006 rates and the 2007 rates for those referees. A comparison of those referees with stats in 2006 and the 2007 season so far suggests there is a relation between the ref and penalties called or home team win-rate. The correlation for penalties called is a fairly positive at 0.269 (but down from 0.309) while the correlation for the home team's win rate took a big drop this week and is now a somewhat positive 0.249 (a big drop from last week's 0.393!)

Referees by penalties accepted per game (followed by home win rate):
Ron's comfortable lead starts to slip a little bit but is still fairly comfortable:
Ron Winter (15.4, 45%)
Walt Anderson (14.7, 64%)
Tony Corrente (13.2, 64%)
Terry McAulay (13.1, 75%)

and at the bottom no major changes:
Scott Green (10.3, 42%)
Bill Carollo (10.2, 58%)
Pete Morelli (10.0, 36%)
Gerald Austin (8.7, 50%)

Referees by home win-rate: if you believe the referee has some influence (perhaps an unintentional tendency) on whether the home team wins, then use this list. Here's the list, again with the penalties per game followed by the home team's win-rate. Terry McAulay takes a comfortable lead at the top with a logjam below:
Terry McAulay (13.1, 75%)
John Parry (12.9, 67%)
Gene Steratore (11.8, 67%)
Larry Nemmers (10.9, 67%)

And at the bottom, a home team for the second straight week actually won a game that Pete Morelli covered! In Pete's games the home team won the first two games this season, lost the next seven(!) and now have won the last two. Scott Green had a chance to take over the bottom spot but the home team won in his game, also. Pete Morelli (who had the worst win-rate for home teams in 2006 for the refs also working in 2007) still has the worst win-rate for home teams. The order of the universe is still intact, it seems.
Bill Leavy (12.1, 43%)
Mike Carey (12.3, 43%)
Scott Green (10.3, 42%)
Pete Morelli (10.6, 36%)

So, if you like the home team, hope for Terry McAulay, John Parry, Gene Steratore, or Larry Nemmers. If you like the visiting team, still hope for Pete Morelli but also good are Scott Green, Bill Leavy, and Mike Carey. Of course, this is only if you think particular referee crews are better for home teams than others.

Here is the information, alphabetically, with total penalties, total yards, and home win-rate:
Anderson, Walt (14.7, 111, 64%)
Austin, Gerald (8.7, 79, 50%)
Boger, Jerome (12.1, 94, 64%)
Carey, Mike (12.3, 94, 42%)
Carollo, Bill (10.2, 74, 58%)
Coleman, Walt (11.7, 86, 45%)
Corrente, Tony (13.2, 108, 64%)
Green, Scott (10.3, 88, 42%)
Hochuli, Ed (11.8, 89, 50%)
Leavy, Bill (12.1, 96, 43%)
McAulay, Terry (13.1, 104, 75%)
Morelli, Pete (10.0, 78, 36%)
Nemmers, Larry (10.9, 92, 67%)
Parry, John (12.9, 108, 67%)
Steratore, Gene (11.8, 91, 67%)
Triplette, Jeff (10.5, 79, 55%)
Winter, Ron (15.4, 114, 45%)

Controversial Referees in the Baltimore Ravens-New England Patriots Game

2007-12-04T06:33:00.000-05:00

It seems like the New England Patriots and Baltimore Ravens are in a bunch of games with controversial referee calls. This time, the Monday night game between them on December 3, 2007. (The Patriots had some controversial calls in a game against the Indianapolis Colts and the Ravens had a controversial field goal decision in a game with the Cleveland Browns.)

Examples include questions about:

Baltimore cornerback Samari Rolle said that head linesman Phil McKinnely (number 110) called Samari Rolle "boy" several times, which angered Baltimore linebacker Bart Scott.
New England's Tom Brady was quoted after the game as saying "a lot of questionable calls" about the game.
Baltimore's Willis McGahee was quoted after the game as saying "we get some bogus calls."
In the fourth quarter, the referees called defensive holding on Baltimore safety Jamaine Winborne to continue the Patriots's winning drive. Baltimore's Chris McAlister qs quoted as questioning that penalty call, saying "It's hard to go out there and play the Patriots and the refs at the same time."
When Baltimore safety Ed Reed intercepted a pass near the end of the second quarter, the referees did not call pass interference against the defender who had reached out to Patriots wide receiver Wes Welker, the intended receiver on the play.

One of my questions is why the journalists who are writing stories about the game aren't analyzing the referee calls to explain whether they think the calls were good or bad. It is the easy way out just to quote players' opinions about what happened. Shouldn't the writers offer their own opinion about what happened on the field, especially for the readers who did not have a chance to watch the game on tv?

A big problem with just quoting players and not offering their own opinion is that many sports leagues including the NFL will penalize players, coaches, and owners for criticizing the referees. Why would journalists rely on quotes from people who have a gag rule that prevents them from sharing their complaints (without risking a fine, of course).

The way that journalists fail to cover the performance of the referees unless the players offer complaints is a big reason that players should not be penalized for commenting on how the referees performed.

Please post your comments on either how the referees did in the game or on whether it seems unfair that journalists rarely offer their own opinion about how well the referees performed, preferring instead just to repeat one or two player quotes.

Later, I will try to look into how Walt Anderson's referee crew's performance this year compares statistically with the other referee crews. His crew is known for being near the top this season in penalties per game, penalty yards per game, and (strangely) the home team's rate of winning games. Walt Anderson's crew was pretty much in the middle of the pack in 2006 for penalties per game.

NFL Referee Statistics (week 12, through games of November 26, 2007)

2007-12-01T07:13:00.000-05:00

Here are the updated NFL referee statistics after week 12 (including games through November 26, 2007):

Possible relationship between the number of penalties called and the rate the home team wins for a particular referee. The strong correlation between the number of penalties per game and the rate the home team wins is still a striking positive of 0.449. Refs who call more penalties are more likely to have the home team win.

Possible relationship between the referee who calls the game and how many penalties there are and the rate the home team wins the game. One way to check on whether the referee has a relationship to how many penalties are called or the rate the home team wins is to compare those statistics in 2007 with the same statistics for those referees in 2006. Then to see if there is some correlation between the 2006 rates and the 2007 rates for those referees. A comparison of those referees with stats in 2006 and the 2007 season so far suggests there is a relation between the ref and penalties called or home team win-rate. The correlation for penalties called is a fairly positive 0.309 while the correlation for the home team's win rate is a pretty positive 0.393!

To see a graph of the scatter plot for 2006 to 2007 referees' home team win rate, try visiting:
http://www.swivel.com/graphs/show/24959489

Referees by penalties accepted per game (followed by home win rate):
Ron extends to a commanding lead after Walt has only 9 accepted penalties in the Minnesota Vikings-New York Giants game:
Ron Winter (15.6, 50%)
Walt Anderson (14.5, 70%)
Terry McAulay (13.4, 73%)
Tony Corrente (13.3, 70%)

and at the bottom no major changes:
Scott Green (9.9, 36%)
Bill Carollo (9.7, 55%)
Pete Morelli (9.7, 30%)
Gerald Austin (9.3, 55%)

Referees by home win-rate: if you believe the referee has some influence (perhaps an unintentional tendency) on whether the home team wins, then use this list. Here's the list, again with the penalties per game followed by the home team's win-rate. Terry McAulay judge edges out Walt Anderson after the home New York Giants lose to the visiting Minnesota Vikings in Walt's week 12 game:
Terry McAulay (13.4, 73%)
Walt Anderson (14.5, 70%)
Tony Corrente (13.3, 70%)
John Parry, Gene Steratore, Larry Nemmers tied at 64%

And at the bottom, a home team actually won a game that Pete Morelli covered! This breaks the visiting team's 7-game winning streak in his games. The Buffalo Bills (5-6) could not beat the Jacksonville Jaguars (8-3) even though Peter Morelli was the referee for the game. Don't worry, though, Pete Morelli (who had the worst win-rate for home teams in 2006 for the refs also working in 2007) still has the worst win-rate for home teams. The order of the universe is still intact, it seems.
Mike Carey (12.9, 45%)
Bill Leavy (12.1, 43%)
Scott Green (9.9, 36%)
Pete Morelli (9.7, 30%)

So, if you like the home team, hope for Terry McAulay, Walt Anderson, or Tony Corrente. If you like the visiting team, still hope for Pete Morelli but also good are Scott Green, Bill Leavy, and Mike Carey. Of course, this is only if you think particular referee crews are better for home teams than others.

Here is the information, alphabetically, with total penalties, total yards, and home win-rate:
Anderson, Walt (14.5, 110, 70%)
Austin, Gerald (9.3, 84, 55%)
Boger, Jerome (11.2, 88, 60%)
Carey, Mike (12.9, 98, 45%)
Carollo, Bill (9.7, 74, 55%)
Coleman, Walt (11.7, 87, 50%)
Corrente, Tony (13.3, 105, 70%)
Green, Scott (9.9, 85, 36%)
Hochuli, Ed (11.8, 90, 55%)
Leavy, Bill (12.1, 96, 43%)
McAulay, Terry (13.4, 107, 73%)
Morelli, Pete (9.7, 75, 30%)
Nemmers, Larry (11.0, 93, 64%)
Parry, John (12.4, 99, 64%)
Steratore, Gene (12.1, 95, 64%)
Triplette, Jeff (10.4, 79, 50%)
Winter, Ron (15.6, 116, 50%)

NFL Referee Statistics 2007 (after week 11, November 19, 2007)

2007-11-22T08:42:00.000-05:00

Here are the updated NFL referee statistics after week 11 (including games through November 19, 2007):

We finally get rid of what we are confident are errors in the NFL's official gamebook. The NFL incorrectly listed "Barry Anderson" and "David Coleman" as referees in weeks 1 and 2, but we put those phantom names to rest now and reassign those games to the referees we believe really handled those games.

The strong correlation between the number of penalties per game and the rate the home team wins is still a striking positive of 0.525. Refs who call more penalties are more likely to have the home team win.

Possible relationship between the referee who calls the game and how many penalties there are and the rate the home team wins the game. One way to check on whether the referee has a relationship to how many penalties are called or the rate the home team wins is to compare those statistics in 2007 with the same statistics for those referees in 2006. Then to see if there is some correlation between the 2006 rates and the 2007 rates for those referees. After 8 weeks, a comparison of those referees with stats in 2006 and 2007 suggests there is a relation between the ref and penalties called or home team win-rate. The correlation for penalties called is a fairly positive 0.301 while the correlation for the home team's win rate is a very large positive 0.461!

Referees by penalties accepted per game (followed by home win rate):
At the top, with a 22-penalty game, Ron Winter takes over top spot from Walt:
Ron Winter (15.8, 56%)
Walt Anderson (15.1, 78%)
Tony Corrente (13.8, 67%)
Terry McAulay (13.5, 70%)

and at the bottom no major changes with Gerald's lead growing very slightly from 0.3 to 0.4:
Pete Morelli (10.1, 22%)
Bill Carollo (10.1, 50%)
Scott Green (9.3, 40%)
Gerald Austin (8.9, 60%)

Referees by home win-rate: if you believe the referee has some influence (perhaps an unintentional tendency) on whether the home team wins, then use this list. Here's the list, again with the penalties per game followed by the home team's win-rate. Walt Anderson takes over the top spot:
Walt Anderson (15.1, 78%)
Terry McAulay (13.5, 70%)
Tony Corrente (13.8, 67%)
Jerome Boger (11.3, 67%)
and at the bottom, Pete Morelli famously extended his lead in the crazy Cleveland Browns overtime victory while visiting the Baltimore Ravens:
Jeff Triplette (10.8, 44%)
Bill Leavy (12.1, 43%)
Scott Green (9.3, 40%)
Pete Morelli (10.1, 22%)

So, if you like the home team, hope for Walt Anderson, Terry McAulay, Tony Corrente, or Jerome Boger. If you like the visiting team, hope for Pete Morelli but be glad if you have Scott Green, Jeff Triplette, or Bill Leavy.

Here is the information, alphabetically, with total penalties, total yards, and home win-rate separated by spaces:
Anderson, Walt 15.1 117 78%
Austin, Gerald 8.9 82 60%
Boger, Jerome 11.3 86 67%
Carey, Mike 13.1 98 50%
Carollo, Bill 10.1 77 50%
Coleman, Walt 11.9 89 56%
Corrente, Tony 13.8 107 67%
Green, Scott 9.3 79 40%
Hochuli, Ed 12.2 93 50%
Leavy, Bill 12.1 96 43%
McAulay, Terry 13.5 108 70%
Morelli, Pete 10.1 80 22%
Nemmers, Larry 11.1 95 60%
Parry, John 12.6 100 60%
Steratore, Gene 12.3 98 60%
Triplette, Jeff 10.8 82 44%
Winter, Ron 15.8 117 56%