MLB umpires need tech help at the plate, says researcher

A study of four million MLB game pitches leads to a call for the league to employ human-software collaboration so umpires can do a better job.

When it comes to calling balls, umps strike out more than you think

Toronto Blue Jays' Vladimir Guerrero Jr. reacts to home plate umpire Adam Hamari after striking out (THE CANADIAN PRESS/Mark Blinch)

"You suck, Ump!" It's a common refrain heard at the ol' ball game.

Major League Baseball fans like to think they know better than the umpires. But what's the reality?

That's a question Mark T. Williams, a professor of finance at Boston University, was inspired to answer.

"For me, the defining moment was last fall in the playoffs. The Red Sox were playing the New York Yankees, and the first base umpire made four bad calls within four innings. I realized I wanted to have the numbers and the backing to understand what is the probability of errors for these various umpires in Major League Baseball," he told Spark host Nora Young.

Mark T. Williams (Boston University)

Using MLB's own data, Williams and his team of grad students analyzed nearly four million pitches over the course of the last 11 regular seasons, looking for how many balls were called strikes and vice versa. He also took age and experience taken into account when ranking the accuracy of all home plate umpires.

The results surprised him.

The study, released on April 8th, concluded that MLB umpires make certain incorrect calls at least 20 percent of the time, or one in every five calls. "The data didn't lie, and fans are correct. Umpires themselves make lots of errors," he said. "And what's interesting about this is not only that umpires make errors, but that they were consistently made."

Williams found some other interesting stats. "When it comes to the two strike bias – when a batter would have two strikes on them – umps were almost 30 percent likely to call a ball a strike. That was astounding to me, that umps would have such bias against the batter," he said. Another surprise for Williams was that the highest error rates came from the older, veteran umpires.

In recent years, MLB has incorporated more technology into the game. There's the radar gun, instant replay, and pitch graphics. But, as Williams has pointed out, "umpires continue to call balls and strikes like they did a century ago when Babe Ruth played."

"On the one hand, Major League Baseball is providing us with more data so we can now track players and the statistics of managers and their success, but it's black hole behind home plate," said Williams.

Williams is not proposing the League replace umpires with robots, but he does think that human-software collaboration should be employed so umpires can do a better job. "The tech-assisted approach is the way to go," he said.


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