In a paper presented at the Joint Mathematics Meeting in January, Bradbury, the economist, and Drinen, the mathematician, noted that the rate of hit batsmen is 15 percent higher in the American League than in the National. Using a computer program written by Drinen, a former college baseball player, the two young scholars mined eight years of detailed play-by-play data on major-league games. After they controlled for pitcher quality, batter quality, game situation and other factors that also contribute to hit batters, they found that the designated-hitter rule itself ”increases the likelihood that any batter will be hit during a plate appearance between 11 and 17 percent.” And in a study of interleague play that they plan to publish next year, the pattern held: in interleague games in which both sides used a D.H., National League pitchers were more likely than usual to hit batters; in games in which pitchers had to bat, American League throwers were less likely to hit opponents with a pitch. In baseball, it seems, the laws of economics govern the diamond as well as the front office.
Thanks to Daniel Pink for the write-up.
Addendum: The Sports Economist has a very good post describing the research. Skip is right to describe the Clemson presentation as lively. I think I stood silent for almost 15 of the first 20 minutes of the presentation as the Economics Department dissected the paper. There’s nothing quite like standing in front of a group of 25 highly intelligent people discussing something you’ve done. I learned a lot in that seminar, and Doug and I are very grateful for all of the feedback we received.