Study: Racial Lines Drawn When Calling Balls And Strikes

By Dave Sessions
Updated: August 14, 2007

FORT WORTH, Tx. — Much to the chagrin of conspiracy-minded baseball fans, no one has ever been able to prove that major league umpires make a disproportionate amount of calls in favor of the Yankees.

But a new study headed by a University of Texas economist, based on a sample of every called ball and strike from 2004-06 — roughly 1.1 million pitches — suggests that umpires hold a slight, inherent bias toward pitchers who share their race or ethnicity.

“I am absolutely sure it’s unconscious,” UT professor Daniel Hamermesh said. “It’s not that the umpire goes, ‘Gee, it’s a white guy; I’m going to help him out,’ or ‘It’s a black guy; I’m going to [cheat] him.’… In this society, people subconsciously prefer people like themselves.”

The study — by Hamermesh, finance professors at McGill and Auburn universities and a UT graduate student — was released Monday.

Through a spokesman, Major League Baseball declined to comment on the study. Rangers general manager Jon Daniels doubted its topic has been discussed much in baseball circles.

“It’s nothing I’ve ever considered,” Daniels said. “I’d be interested to read the study, but it certainly never dawned on me.”

Among the study’s findings: White umpires called strikes on 32.06 percent of pitches from white pitchers, but only 30.61 from black pitchers. There were only five black and three Hispanic umpires, but their numbers were similar.

When both starting pitchers or neither starter matches the umpire’s race, the home team wins 53.8 percent of the time. When the home team’s pitcher’s race matches the umpire’s, the home team wins 55.6 percent of the time.

What’s more, the alleged preferential treatment disappeared when umpires were under more scrutiny — whether it was electronic monitoring by the QuesTec system in 11 of 30 ballparks, a large attendance or a so-called “terminal” pitch in a three-ball or two-strike count.

“To me, it said how easy it is to reduce it when you have more scrutiny,” Hamermesh said. “I was surprised at how quickly it disappears in QuesTec parks.”

Although the differences are slight, Hamermesh said the massive volume of the pitch sample shows it’s nearly impossible to be a coincidence.

“It’s possible there would have been no effect,” he said, “but you can’t ignore the fact that we have the huge data and we find something there…. How can you manipulate a million pitches?”

The authors of the study examined pitch data from and classified pitchers and umpires by race — not an easy task, Hamermesh said, but one that, if done incorrectly, would have made the discrepancies between matched-race and nonmatched-race calls smaller.

The study also didn’t address whether pitches were actually called according to MLB standards, because “called balls and strikes are inherently subjective,” Hamermesh said.