Biased Umps

I heard about this study the other day on NPR. Here is what Newsweek has to say about it:

“A new study by a professor at the University of Texas at Austin suggests that home plate umpires call balls and strikes more favorably when the pitcher is their same race, Time magazine reported.

The research team led Daniel Hamermesh, professor of economics, found that umpires call strikes more for pitchers of their race and balls more when the pitcher is of another race, Time said.

The study found that the disparity occurred in 1 percent of pitches. The researchers analyzed 2.1 million umpire calls between the 2004 and 2006 seasons, Time said.

“One pitch called the other way affects things a lot,” Hamermesh said. “Baseball is a very closely played game.”

Hamermesh added that even a slight bias by umpires will affect the kinds of pitches that pitchers make if they believe they are getting squeezed by the umps. Pitchers who are getting balls called too much might start throwing over the middle of the plate more, thus resulting in batters getting fat pitches to hit, Time said.

Seventy-one percent of major-league pitchers and 87 percent of umpires are white. ” more…