Missing Corners

So far, all of the analysis done on the strike zone has intentionally ignored pitches on the corners because there’s no way to know if they are being called balls because they’re too high or too wide. The downside to this is that it assumes that the strike zone is really a square, or at least the same distance from the plate at the knees as it is at the belt. No such luck. Here’s what it really looks like:

Not even remotely rhombus! That’s every called strike from 2007 remapped to an average strike zone and given colors by density. As you can see, umpires are much more inclined to give a pitch off the plate to the sides (and slightly more to the left, because they give lefties the shaft, but that’s another story).

There are two ways of looking at this. You could say umpires generally call way too many strikes to either side but don’t give the corners, or that they call the corners very precisely but are willing to expand to either side on pitches if they are (vertically) right down them middle.

It makes sense- a pitch comes in that is both a little low AND maybe a little outside, the human mind are going to be less inclined to call it a strike than if it was outside but otherwise perfect at the belt, even if the actual distance from the strike zone is the same. In the umpire’s defense, those are also pitches that are next to impossible to hit if they’re off the plate. Here’s every pitch from 2007 that batters turned into a hit charted in the same way:

Lesson for today? Don’t throw it right down the pipe, meat. (Why does he keep callin’ me Meat? I’m the one driving a Porsche…)

Not that this comes as a big surprise, but it’s interesting to see how quickly hits drop off to the four corners. So which came first- do hitters not swing at those pitches because they’re called balls, or have umpires evolved to not call those pitches strikes because they know batters can’t hit them?