The science of umpiring

Blindspots behind the plate.

What’s in the brain of an expert umpire?

If you’re Yankees manager Aaron Boone, you’d probably say “nothing.” Kidding! Well, but it does seem that, for whatever reason, there’s been more scrutiny on umpiring in the early days of this Major League Baseball season than in other seasons in recent memory. I don’t know why! Everyone just seems … testier.

But I think it’s helpful to know why umpiring is not — and might never be — as perfect as fans and players and managers often expect. In this week’s newsletter, I’m going to offer three science-based reasons why. One is grounded in neuroscience, another behavioral psychology, and the third is … well … climate change.

I’m not here to dunk on umpires. To the contrary, I hope this offers some perspective as to why umpiring is so hard — or, at least, what umpires are up against. Some (but not all of it) is out of their control.

A number of studies, for example, have circled around one umpiring blind spot: Left-handed pitchers.

Here, I’ll give umps a pass. In general, left-handedness bestows a slight advantage to performers in many sports because left handers are less common, therefore making them harder for opponents to visually anticipate. Umpires, it seems, are just as fallible. A review of PitchF/x data from the 2010-2013 seasons found that, on average, umpires shifted their strike zone by several inches to the left during matches between a left-handed pitcher and a right-handed hitter.

A recent study done by researchers in Taiwan recruited 16 professional umpires from the Chinese Taipei Baseball Association to undergo a brain scan while being asked to call balls and strikes from inside the bore of an fMRI machine. Sure enough, behaviorally, even expert umpires were less accurate judging pitches thrown by a left-handed pitcher than a right-handed pitcher. What’s interesting is what the fMRI scans revealed about why that might be the case.

What an umpire sees while getting his brain scanned

An umpire’s blindspot

The brains of the expert umpires responded differently to pitches thrown by a lefty vs. a righty. When a right-hander threw, there was “substantial engagement” of brain regions known as the Action Observation Network (AON), cerebellum, and dorsal striatum (caudate) — all areas involved in decision-making and the perceptual processing of visual information. When judging pitches from a southpaw, “these activations were weaker,” the researchers observed. The suggestion here is that seeing pitches from a lefty did not trigger the same forceful and decisive judgments as pitches from a righty.

The blue/green shading are regions of activation in expert umpires while judging balls & strikes.

There was also noticeably lower activity in a region known as the premotor cortex, an area shown to be heavily involved in predicting dynamic events — and thus preparing the body to move. That implies that umpires weren’t just having more difficulty processing what they were seeing as it was unfolding. They were less able to predict the trajectory of a ball or strike thrown by a left-handed pitcher, which caused them to be less decisive about what the pitch actually was.

The evidence that handedness seems to deceive umpires’ brains helps to understand why it might seep into their pitch-calling behavior. The study was a small sample size, and an experienced ump should be comfortable enough seeing left-handed pitchers to be able to mitigate (or compensate) for any perceptual lags.

The Umpire’s Fallacy

But the neural underpinnings of an umpire’s decision-making only explains so much.

Umpiring is also a mind game. There’s pressure, stress, fatigue, ego — all hallmarks of a competitive athlete. Except that fans aren’t paying to watch you perform. In fact, they hate it when you get in the way.

One of the most fascinating studies on umpiring was published in 2016 by economists Daniel Chen, Tobias Moskowitz, and Kelly Shue that examined a phenomenon known as the “gambler’s fallacy,” a term first coined by Daniel Kahneman and Amos Tversky in the 1970s.

The “gambler’s fallacy” is the well-documented tendency for people to assume that, if something has occurred more frequently than expected, it is less likely to occur in the future. A gambler at the roulette wheel, for instance, might expect that the ball will land on a Black number following a streak of Red numbers, even though the odds of it happening are unchanged. It’s the age-old misconception that something is “due.” And the economists found that this bias against streaks can easily creep into our decision-making.

They highlighted three examples. A review of more than 150,000 U.S. asylum court decisions by 357 different judges found that they were less likely to grant asylum if they had just approved the previous applicant. They became even less likely to grant asylum if they had approved the previous two applicants. It’s an incredible finding.

It matches what they found about loan officers who make decisions on underwriting enterprise loans: They’re more apt to deny the current loan application if the previous one just got the green light. Ouch.

And so you might already guess where this is going with baseball umpires. Indeed, they are less likely to call a pitch a strike if the two most recently called pitches were also strikes. The effect was even bigger if the third pitch in the sequence was a “borderline” strike — pitchers are not going to get that call.

Let’s pause for a second to soak in the implication of this. An umpire has an implicit strike zone. He has a brain that can visually process and make decisions on whether a pitch falls within that strike zone. And yet, 2-5 percent of the time, he will overrule both of these concepts simply because it would seem too weird for three strikes to be thrown consecutively. Wow.

Moskowitz, et. al, analyzed 127 different Major League umpires in their dataset. Every one of them fell prey to the gambler’s fallacy.

Something in the air

We’ve talked about the neural processing of umpires, and how it may be undermined by their own psychological biases. But what about when an umpire’s decision-making on a certain day is simply … cloudy?

That was the notion behind a 2018 study in the Journal of the Association of Environmental and Resource Economists, which looked at how air quality might impact mental performance in a highly focused task—in this case, baseball umpiring. The researchers analyzed more than 623,000 pitches called by 86 umpires between 2008 and 2015 and tracked whether pollution levels in the area (as measured by the nearest monitoring station) had any influence on their accuracy.

They found that a 1 ppm increase in the amount of ambient carbon monoxide in the air around the ballpark caused an 11.5 percent increase in the propensity for umpires to make incorrect calls, or roughly 2 incorrect calls per 100 decisions. An increase in other, so-called fine particle pollutants in the ambient air likewise contributed to a tougher night behind the plate.

So the next time an ump blows a call against your favorite team, at least now you’ll have some ideas as to why.

Links

Are women better endurance athletes than men? … When is the best time to work out? … New research on why athletes shouldn’t rush back from ACL tears … The elusive “fourth dimension” of endurance … Dehydrated athletes run slower … English cricket club using AI to select lineups … Is Athletes’ Sixth Sense Real, or a Postdictive Reconstruction? … They’re young and athletic. They’re also ill with POTS … Keep winning at tennis? You “see more images” per second than others … Training strategies of 10,074 athletes from 121 countries based on human development index in early COVID-19 lockdown … Discus thrower breaks oldest track & field world record … Why cocaine is considered performance-enhancing for athletes

References

Chen, Yin‐Hua, and Shih‐Kuei Huang. "The influence of pitcher handedness on pitch‐calling behavior: Insights from fMRI study on baseball umpires." Psychophysiology 61.3 (2024): e14501.

Chen, Daniel L., Tobias J. Moskowitz, and Kelly Shue. "Decision making under the gambler’s fallacy: Evidence from asylum judges, loan officers, and baseball umpires." The Quarterly Journal of Economics 131.3 (2016): 1181-1242.

Deshpande, Sameer K. and Wyner, Abraham. "A hierarchical Bayesian model of pitch framing" Journal of Quantitative Analysis in Sports, vol. 13, no. 3, 2017, pp. 95-112. https://doi.org/10.1515/jqas-2017-0027

Archsmith, James, Anthony Heyes, and Soodeh Saberian. "Air quality and error quantity: Pollution and performance in a high-skilled, quality-focused occupation." Journal of the Association of Environmental and Resource Economists 5.4 (2018): 827-863.

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