Calling Balls and Strikes in the Age of Measurement: What Would Deming Say About ABS?

Deming's review of ABS

In the long, storied history of Major League Baseball, few responsibilities have remained as sacred and as human as the umpire calling balls and strikes. For over a century, the strike zone has lived in the eyes, judgment, and consistency of the umpire while accepting the risk of making mistakes. That is, until now.

If you have watched or been to any baseball game in 2026, you have been introduced to the Automated Ball-Strike (ABS) Challenge system that defines a strike zone in a consistent and repeatable 2D rectangle. Horizontally, this rectangle judges if the pitch is within the 17” that represents the front edge of home plate. Vertically, the top of the rectangle is set at an elevation that is precisely 53.5% of the batter’s height, and the bottom that is 27%. The tolerance of whether a pitch is within or outside of the window is within 0.1”. For the first time in baseball history, we are not just debating accuracy and singing "Three Blind Mice"; we are measuring it. And if we are measuring it, having a conversation with W. Edward Deming on this subject would be fantastic.

DEFINE: ABS in baseball

The introduction of ABS currently does not remove the umpire, but instead introduces a feedback loop when the umpire’s decision is challenged. Players on offense or defense can challenge the umpire's decision and receive an objective check against human judgment. The question is no longer, Did the umpire get it right?, but instead, What does the system reveal about variation, consistency, and improvement? Baseball has brought DMAIC into the game.

With the ABS, the problem existing between a batter and a pitcher is being solved differently. The umpire is attempting to maintain the authority of the pitch while being measured against a machine. The batter is now ensuring the fairness and repeatability of a strike zone. The catcher’s ability to frame a pitch is not as valuable as it was previously. The pitcher has now established a trust that their pitching execution is rewarded consistently. Historically, the strike zone has been subjective. ABS is attempting to solve the problem of a strike zone across situations and umpires.

MEASURE: The First True Baseline

ABS is a breakthrough in the ability to measure. ABS introduces a measurable standard, something Deming insisted was essential but often misunderstood. Measurement, in his philosophy, is not about judgment, but instead about understanding variation. Deming would point out that umpire accuracy rates can now be tracked to recognize patterns (high/low, inside/outside) and analyzed in real time. Deming would most likely say that the danger of this technology would be turning measurement into evaluation rather than insight.

Not everything that can be measured matters—and not everything that matters can be measured. Often noted that Albert Einstein said this

ANALYZE: Four Perspectives on Variation

From the umpire’s perspective, ABS exposes variation that was previously hidden. Deming would recommend that umpires distinguish if their performance has a common-cause variation (natural human inconsistency) or special-cause variation (e.g., fatigue, positioning, pressure). This variation should challenge the umpires to ask themselves whether they are applying consistent strike zone definitions across levels. Are they positioning themselves consistently behind home plate for each batter, regardless if they are left-handed or right-handed?

From the batter’s box, the batter should recognize that ABS represents fairness. But it also introduces a strategic decision on when you should challenge and how confident you are in your perception. Deming would note that the batter is now part of the measurement system, versus being the result of a subjective judgment. The batter’s behavior now becomes a data point versus an ejection after arguing a call, revealing perception gaps between human judgment and technological reality.

Perhaps no role is more disrupted than the catcher. Framing has been a skill refined over the decades, with the likes of J.T. Realmuto from the Phillies often being recognized as being one of the best in the game. Deming would ask J.T. if the art of framing diminished its value with the introduction of ABS? Obviously, with challenges left, having the ability to frame is less valuable. However, framing when challenges no longer exist remains a critical skill that can influence a call.

For pitchers, ABS is clarity and support of execution should equal outcome. After a few months of measurement, Deming would look deeper into the data to determine whether ABS has reduced variability in pitchers’ pitch selection or if ABS has bred a new type of pitches. Pitchers may now attack edges differently, especially the top, knowing the zone is fixed.

When you have performance anxiety, it makes you more self-conscious. And it starts to take what might be routine that you do autopilot, and make it more salient. So that you're thinking through, what am I supposed to do now? It interferes with the ability to just go through the motions.

IMPROVE: Now what should we do with the analysis

Improving is where I believe Deming would lean in hardest. Deming would most likely not offer an opinion if ABS is making the game better or worse, but instead simply ask if ABS is making the system of calling balls and strikes more accurate. ABS introduces the risk of an over-reliance on technology and an erosion of human elements that define the sport. The introduction of ABS is not just a technological shift, but instead it is a cultural one. Once you measure something, you can make a change. Umpires will adjust their zones, players will adapt new strategies, and fans will recalibrate expectations.

You have taken a skill that is mostly automated (by human), and you have all of a sudden made it conscious. And trying to think through the steps actually, with your ability to effortlessly execute those steps through autopilot. Adam Grant, The Curiosity Shop, Overconfidence and the Art of Knowing Yourself

CONTROL: ABS and the impact on the game

ABS is not about replacing the umpire, but instead about revealing the system. For the first time in baseball history, the strike zone is no longer just being called. It is studied, and in that shift lies both opportunity and risk. If approached through Deming’s lens, ABS becomes more than technology by becoming a case study on how we balance human judgment, data, and continuous improvement. And maybe, just maybe, it teaches us that our love of baseball was never about perfection but instead about understanding that variability should be part of the game.

I think any time you do something well automatically, as you start to analyze it and describe it you may take a step backwards before you can take two steps forward. Adam Grant, The Curiosity Shop, Overconfidence and the Art of Knowing Yourself