I Love New Metrics!

Except when I don’t.

This story is about O-Swing %, which measures the number of times a batter swings at pitches out of the strike zone. The writer says that O-Swing % is really interesting, and then goes on to prove (unless his numbers are wrong) that it is pretty much meaningless.

What is actually interesting is that the writer does a decent job of demonstrating why the apparently broad swing in O-Swing % numbers is meaningless. It boils down to the fact that some batters swing more, and so they hit the ball more. While some batters swing less, and hit the ball less. Consider 0-Swing % exhausted, at least for now.

When there is reliable pitch location information there will doubtless be information derived from these numbers that will be of interest, but it certainly won’t be simple or absolute. The game isn’t simply a matter of cause and effect, but a complex system of adjustments and readjustments that change how everything happens. It seems to me the miracle is that the game is played on the same sized field now as it was 100+ years ago. In that context, the variation in results should lead us to explore what changes have been made.

But that has nothing to do with O-Swing %.