Other Sites Tracking NFL Referee Performance

Visit some others sites that are also tracking NFL Referee performance:

Fox Sports is providing basic information about referee performance for calling penalties (including penalties called and penalties accepted):
http://msn.foxsports.com/nfl/sortableStatsOfficials

Mike Sando at the Seattle News Tribune is tracking fascinating statistics: penalties called, replay challenges made, and replay challenge reversal rates. He is also tracking replay challenges by coach.
http://blogs.thenewstribune.com/seahawks/?cat=179

Mike Sando wrote that there is variation among the referees about how many penalties they call per game. He wrote that " These things tend to even out some over the course of a season."

One question is whether that is true or not. My feeling is that the tendencies do not even out over the course of a season, but of course they do somewhat compared to the largest stretches (just as someone on a long streak of any particular statistic will at some point come back to earth somewhat, but often will not "even out" over time). We will have to run some statistics on that.