This article is part of our The Z Files series.
One of the unfortunate repercussions of more people using next level stats is more people are misusing next level stats. I realize I can often come off as pedantic; maybe it's the years of scientific training. That said, employing a stat for which one is not completely familiar is lazy. Assuming it means something is even worse.
The current example of this is maximum exit velocity. It's referenced in both the mainstream and fantasy analysis. Yeah, it's cool. Major League batters hit the ball wicked hard. However, it either has no predictive value, or there are better indicators. Yet, it's bandied about as if it reveals something more than the batter happened to hit the snot out of the ball on that particular swing.
Intuitively, what should maximum exit velocity imply? One of the common assumption is a high maximum exit velocity portends a high batting average.
Here are the correlation coefficients, comparing maximum exit velocity and BABIP for every hitter with at least 300 plate appearances from 2017-2019. A coefficient of 1 signals perfect direct dependence, -1 means perfect indirect dependence while 0 says the relationship is completely random.
Sorry friends, it doesn't move the needle. How about power, does maximum average velocity correlate to power, expressed in terms of homers per plate appearance? Let's compare it to overall exit velocity and average exit velocity on fly balls.