In short, the authors claim that home-field advantage is explained by the psychological effects of the crowd on the officials. They claim that referees draw information from the reaction of the crowd, especially when the call is uncertain.
The replacement referees that the NFL is using give us an additional chance to test this. Given that this advantage manifests itself in uncertain, subjective calls, we expect a study to show that this effect is magnified in the presence of replacement officials, who will presumably be of worse quality than the typical NFL official and thus be uncertain about a higher number of calls.
Until the end of the referee lockout, then, I will be tracking several factors that Moskowitz and Wertheim claim demonstrate this principle clearly:
- Turnovers (specifically, fumble recoveries)
- Calls overturned by instant replay
- And, of course, home team record.