Jeff Sullivan has an interesting look at the strike zone at SB Nation today, looking at which pitchers and teams tend to get big strike zones and which pitchers and teams tend to get small strike zones, looking at balls and strikes called compared to the flat PitchFX strike zone.
There are lots of caveats and interesting things in the article, so you should take the time to read the whole thing. Some of the “most-screwed” pitchers are guys like Charlie Morton and Justin Masterson, so it’s possible that late-breaking pitches like sinkers affect how umpires call the strike zone. It’s really hard to know how much of this correlation is meaningful and how much of it is coincidental and really, the only way to learn these sorts of things is to keep looking at the data.
I find the last table very interesting, though, and one thing stands out pretty strongly to me. As Sullivan says, the average team loses 5.6 strikes per 1000 pitches because the real strike zone is different than the PitchFX strike zone. If we use that as a threshold, there are 13 teams above that line in 2012, and 10 of them had a winning record in 2011. Of the 17 teams below that threshold, only three had a winning record in 2011.
There are a million possible explanations for this and I’m always the guy trumpeting that CORRELATION DOES NOT EQUAL CAUSATION and I am in no way advocating a conclusion or drawing a conclusion for myself here, but if you tend to think that an umpire’s preconceived notions about a baseball team affect the way that they umpire the game, well, this doesn’t exactly disprove that idea.
I fully realize that I’m playing “I’m not sayin’ I’m just sayin” here and I’m OK with that.