Touching BasesJuly 26, 2010
Working Hard or Working Fast?
By Jeremy Greenhouse

"The wrong way, but faster." Max Power

I could point to a dozen articles discussing the varying shapes and sizes of the strike zone, but when my friend Don asked whether umpires really change their zone depending on the score, I drew a blank. Factors such as the identity of the pitcher and the ball-strike count influence an umpire's process, but only so that he can do the job to the best of his ability. Yet for some reason, it's been casually accepted by some that umpires might be so unprofessional that they call a larger strike zone in a blowout to quicken the pace of the game.

Fortunately, this assertion is not backed up by any evidence, as umpires appear to call consistent zones depending on the score. Below, I plot the 25%, 50%, and 75% contour lines for called strikes based on four different score differentials. The zones are jumbled and mostly indistinguishable, so, on the whole, umpires do not call to the score.


Perhaps there are some umpires who regularly schedule early dinner reservations, but the only ump I'm willing to openly critique is the only umpire who invites such criticism: Joe West.

I graphed West's strike zone at the point where he is equally as likely to call a strike as he is a ball. I also dug up the two Red Sox vs. Yankees games that West umpired, and plotted those ball/strike calls. West, you may remember, publicly denounced the length of these games. However, I found no evidence of bias. If anything, West has squeezed batters in Sox/Yanks games and batters in blowout games (blue line).


Umps aren't alone in being accused of unprofessionalism. Weeks ago, Patrick Sullivan* questioned the commonly-held wisdom that players try to get out of the ballpark ASAP during getaway games. It's hard to believe that batter would swing at bad pitches just because they're playing in the final game of a series, but that's what I checked for.

*You can follow Sully on Twitter, if only to observe him incessantly hound the insufferable Boston media. For example, "Shaughnessy on May 9: 'Beltre is emerging as an Edgar Renteria or Rasheed Wallace, take your pick.'"

Getaway Rest of Series
Time 2:56:27 2:55:15
Day Game 68% 14%
Innings 9.20 9.16
Runs 4.54 4.67
Hits 8.94 9.03
Errors 0.60 0.60
P/PA 3.83 3.81

You'd be hard-pressed to find statistical evidence that umpires and players sacrifice quality for expediency.


Is there a way to check how Umps call games in different weather? I'm thinking of mainly heat. Do they call a bigger zone in higher temps versus something more comfortable temp-wise?

Mike, I never heard of that. I do have game-time temperature data, so I could check that. Not sure I'll get to it.

By the time they get to the majors, they've called 50 billion pitches.

They'd have to really struggle to control thier automatic ball/strike decision.

Not that they can't, but to do so for more than one or two batters would be tough.

Jeremy, is it possible to check what umpires call to pitchers? I'd be highly inclined to believe they are more likely to call strikes that aren't against pitchers. I think the same thing is true on 3-0 counts.

I think the perception (and at the moment it's only a perception) isn't so much that the umpires change the zones in blowouts, but rather that they call critical pitches differently.

Your analysis weighs all pitches equally, but there isn't much incentive for an umpire to change his entire strike zone (calling a few extra strikes early may not do much, as batters ahead in the count likely will swing away in blowouts).

If the perception is true, umpires will have their regular strike zone, and then on, say, a 3-2 pitch late in a blowout, call an easy ball a strike "to keep the game moving and get out of there". A large sample size of all pitches wouldn't reveal this, as I think the perception comes from irregular but egregiously wrong calls in these key counts.

I'm not sure there would be any way to statistically test this. Perhaps you could qualitatively choose games that are blowouts, pull up the zone records of the umpire in question, and then see if the umpire departs from his regular convention on key pitches? It would take a lot of work, I imagine.

But good job looking into this, it makes a lot of sense to investigate what is viewed as an almost universal truth.