Home Field Advantage

Tom Meagher has an excellent article at The Hardball Times breaking down the cause of home field advantage in MLB. The results are quite shocking. The home/away difference in balls and strikes explains about two-thirds of home field advantage. Why is this?

Are umpires really helping out the home team? Are pitchers more familiar with the pitching mounds at home? Are visiting batters having a harder time seeing the ball or reacting to it? Is fatigue affecting the results?

It may be significant here that the total number of balls in play (bip) per plate appearance (pa) does not differ much – the home/road factor for bip/pa was 1.0079 in the NL and 1.0002 in the AL. That leads me to believe that the major change in walks versus strikeouts is related to judgment of whether a pitch is a ball or strike – either the batter’s poor judgment, induced by lack of familiarity with the hitter’s backdrop, or the umpire’s judgment, giving better calls to the home team.

Interesting stuff here. I expect there is more to come.

2 Responses “Home Field Advantage”

  1. Anonymous says:

    I would imagine that how comfortable players feel in their own parks would also play a part in explaining these differences. If we look at other sports like soccer, all fields are the same size (physical conditions tend to be exactly the same) and although the same umpire (referee in this case) argument coul be used, the big difference seems to be that the home team has thousands of people cheering for them. This is one of those unmesurables that us economists have a hard time dealing with.

  2. Anonymous says:

    Well, first, the home field advantage in baseball isn’t that great, certainly compared to other sports. Basically, the home team wins slightly more than 50% of the time. You would sort of expect that simply from the fact that the home team is more comfortable, not traveling, more familiar with the park, own fans, etc. I don’t really see a big controversy here. I would be more interested to see if there is a larger home field advantage in interleague games, including the World Series because of the DH or lack thereof.

    I don’t see why an umpire’s ball and strike calls would change that much. You might expect that in playoff games where the crowd is really loud, but, for the most part, I think baseball crowds are more laid back. I can’t see a crowd intimidating an umpire.