Jerry Kim

Seeing Stars: Matthew Effects and Status Bias in Major League Baseball Umpiring

Coauthor(s): Brayden King.

Despite a growing body of research about the Matthew Effect and status, we still know little about the cognitive biases that underlie the ability of high status actors to accumulate advantages over their lower status peers. In this paper we test the assumption that actors' status biases evaluators' judgments made about those actors' quality. We posit that high status actors benefit from over-recognition of quality, wherein evaluators are more likely to erroneously attribute high quality to an actor's performance, and that evaluators systematically and erroneously under-recognize quality in low status actors. Using unique data from Major League Baseball umpires' evaluation of pitch quality, which allow us to observe the difference in a pitch's objective quality and in its perceived quality as judged by the umpire, we show that umpires are more likely to over-recognize quality in high status pitchers and under-recognize quality in low status pitchers. Ambiguity and the pitcher's reputation as a "control pitcher" moderate the effect of status on umpire judgment. Further, we show that umpire errors resulting from status bias lead to actual performance differences, decreasing the probability that high status pitchers allow players to get on base and increasing the likelihood of winning the game.

Exact Citation:
Kim, Jerry, and Brayden King. "Seeing Stars: Matthew Effects and Status Bias in Major League Baseball Umpiring." Columbia University, 2012.
Date: 2012