Why do home teams have an advantage?

Inspiration from a cheering crowd? Better focused and prepared because they did not have to travel?  More familiar with the stadium and its idiosyncrasies (e.g., Fenway Park)?

None of the above, says Tobias Moskowitz and economist at the Chicago Booth School of Business.  The real reason, Moskowitz argues in a book with Sports Illustrated journalist Jon Wertheim, is referee bias.  In particular, bias in making calls that happen at a critical time of the contest.  Moskowitz explains why in this interview on NYT website.  The reasoning is quite fascinating, as he rules out other possible explanations of home time advantage one by one.  For instance, when two teams from the same city play in any sport, the home field advantage is the same as it is overall -- so travel really cannot be an explanation.

Why do refs favor the home team in clutch situations? 

Psychology finds that social influence is a powerful force than can have great impact on people’s decision-making, even if they are unaware of it. People tend to converge their opinion toward a group’s opinion both because of social pressure (the desire to fit in) and for informational reasons (the group may be better informed than the individual). Basically, we think officials are seeing the game the home team’s way both because they may have a subconscious desire to relieve pressure from the yelling crowd and because they may be taking subtle cues from the crowd about what the correct call should be.

Luckily this weekend the Final Four is being played at a truly neutral site, in contrast to last year when mighty Butler got to play in its hometown.