By Chris | August 20, 2008
Sports are fun, and awash in data. It shouldn’t be surprising then that economists love to study them. For example, the best-seller Freakonomics discussed cheating in sumo wrestling and academics recently examined point shaving in professional basketball. Blogs such as Sabernomics and The Sports Economist are devoted to the application of economics to sports. While perusing Sabernomics, I was intrigued by a post noting that David Ortiz’s batting performance improved after the subsequent batter, Manny Ramirez, was traded to the Dodgers. Apparently, there is significant evidence that being followed by a power-hitter like Ramirez decreases the likelihood you will be walked, but also decreases your hitting performance. This runs contrary to the conventional wisdom that you’re protected by batting in front of a slugger. What is the story here?:
The gains a batter receives from seeing more pitches in the strike zone can be offset by the pitcher making those pitches more difficult to hit. Pitchers regulate their effort throughout a game in order to conserve energy for important moments, such as facing Ortiz with Ramirez on deck. An improved Ramirez may cause Ortiz to be walked less, but Ortiz will be seeing tougher pitches to hit.
As an aside, I’m a big Minnesota Twins fan. They are currently one game behind the first-place White Sox in their division and 1.5 games behind Boston for the wild card (Standings). Over the course of the season, the White Sox and Twins will have schedules of very similar difficulty. However, at an given time, the schedule difficulty to date may be skewed. If the Twins played lots of hard teams early in the season, and the White Sox played relatively easy teams, than the current record isn’t very informative. I decided to go back and compare the record of the Twins and White Sox against common opponents. If the Twins had played the Royals 10 times and won 8 of the games, and the White Sox had played the Royals 20 times and won 12 of the games, I pretended that each team had played the Royals 10 times and the White Sox had only won 6 of their games. In other words, I wanted to estimate what each team’s win percentage would be if they had exactly the same schedule. The result: The Twins won 54.2% of such games and the White Sox won 57.8% of the games. I’m still hoping for the pennant. That is the great thing about being a fan, no one expects you to be rational. (See the Excel file).