Why does the home team win?

Officials are scared of the crowd

So we looked at how games are called and that’s where the data went berserk. Yellow and red cards in soccer, calls in the NFL before and after replay’s implementation, called balls and strikes in baseball — that’s where we saw games are called totally differently based on where they’re played. And the more attended the games are, the more striking the bias.

I’m looking forward to seeing the book (soon, I think) and the data. But this does reinforce something that’s been floating around in my head for a long time (because I read it somewhere): Most (if not all) of the home-field advantage is the result of the officials subconsciously wanting to avoid getting yelled at by the fans. And it wouldn’t take much to cause a measurable effect. There are how many pitches in the average baseball game? Something like 300? And how many of those could reasonably be called a ball or a strike?