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Are Umpires Racist?

Umpires call more strikes for pitchers of their own race. Fact or fiction?

“Red Sox Yankees Game Boston July 2012″ by Victorgrigas – Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons
Source: “Red Sox Yankees Game Boston July 2012″ by Victorgrigas – Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons

Good news for Major League Baseball umpires: You may not be as biased as previously thought.

Research appearing in this month’s print issue of the Journal of Sports Economics disputes an earlier finding that umpires give preferential treatment to pitchers of their own race.

Here is a brief synopsis of the debate. In 2011, University of California San Diego professor Christopher Parsons and his collaborators published an influential paper in the American Economic Review titled, “Strike Three: Discrimination, Incentives, and Evaluation.” Analyzing over 2 million MLB pitches from 2004 to 2006, they found that umpires called more strikes when the race of the pitcher matched their own race. White umpires called more strikes when officiating white pitchers; black umpires called more strikes when officiating black pitchers.

Disturbing results, to say the least.

At the time, Parsons’ 2011 paper was added to the growing number of studies exposing biases in professional sports officiating. Other research, for instance, has found that soccer referees award more penalties to home teams, NHL teams receive more penalties when they wear dark-colored uniforms, and shorter NBA referees call more fouls.

And, for a league with a long history of wage discrimination, Parsons’ research suggested that the problem might be worse than imagined. They write, “the fact that over 90 percent of the umpires are white implies that the measured productivity of non-White pitchers may be downwardly biased.”

But not everyone was convinced by Parsons’ results. Thus, a group of researchers led by University of Illinois professor Scott Tainsky sought to replicate Parsons’ findings using a larger data set.

In their study, researchers analyzed MLB pitches from 1997-2008 (over 8 million pitches compared to the 2 million pitches analyzed by Parsons). Looking at the broader data set, Tainsky and his colleagues found no evidence of racial discrimination among MLB umpires. If anything, the results trended in the direction of reverse-discrimination.

Why the difference in results? To answer this question, Tainsky and colleagues limited their sample range to the 2004 to 2008 MLB seasons and conducted the same statistical tests as Parsons. Under these specifications, they were successful in replicating Parsons’ results. However, more accurate statistical testing (one that accounted for pitchers’ prior accuracy) again revealed Parsons’ finding to be spurious.

Although the final word may not yet have been said, it appears that, in this case, the bias was exhibited by the scientists, not the umpires.

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Garicano, L., Palacios-Huerta, P. & Prendergast, C. (2005). Favoritism under social pressure. The Review of Economics and Statistics, 87, 208-216.

Gift, P., & Rodenberg, R. M. (2014). Napoleon Complex Height Bias Among National Basketball Association Referees. Journal of Sports Economics, 1527002514535168.

Parsons, C. A., Sulaeman, J., Yates, M. C., & Hamermesh, D. S. (2011). Strike three: discrimination, incentives, and evaluation. The American Economic Review, 1410-1435.

Tainsky, S., Mills, B. M., & Winfree, J. A. (2013). Further examination of potential discrimination among MLB umpires. Journal of Sports Economics, 1527002513487740.

Webster, G. D., Urland, G. R., & Correll, J. (2012). Can uniform color color aggression? Quasi-experimental evidence from professional ice hockey. Social Psychological and Personality Science, 3(3), 274-281.