Fun With Arbitrary Statistics

There are a lot of great statistics in baseball these days. They measure everything! Swing path tilt? Contact point against center of mass? Exit velocity? Hard-hit rate on opposite field line drives? You can get a report on any of those things at the wave of a few fingers. Expected wOBA? Barrel rate? There are acronyms and stat blends and projection aggregates for days. It’s analysis paralysis; the hard part isn’t finding stats to describe hitters, but figuring out which ones not to use.
I don’t have a foolproof method for seeing through all the noise for you. But I do have a fun experiment in how to work with statistics in such an overwhelming environment. I want to suggest a method that I call, These Things Are Good. Basically, it boils down to this: Come up with some statistics that you think are good without pre-determining which players you’re looking for, measure how good the entire league is at your statistics in question, and see what shakes out.
How should we do this in practice? I started by saying that I think pulling the ball when you hit it in the air is good. That gives me the first statistic I care about: air pull rate. I turned that into standard deviations for every player in baseball so that we could compare apples to apples across multiple statistics, then started looking for who the standouts were across all categories.
Air pull rate is nice, but it’s certainly not the only statistic that I’m interested in. Next, I wanted guys who hit the ball hard when they put it in the air. After all, exit velocity matters far more when batters can elevate. I did the same thing and put that in z-score terms via standard deviations. If you’re wondering what kinds of hitters these two categories identify, Kyle Schwarber, Griffin Conine, and Junior Caminero are the top three. Read the rest of this entry »






