A little over a week ago this site looked at who was responsible for getting ground balls. A reader wondered if we could plug batting stats into this method, so here it is. Let me remind you of the methodology:

To study this, I selected a group of pitchers that gathered 400 IP from 2002-2004. There were 101 pitchers in the group, and I divided them into quartiles on the probability of a ground ball. Quartile 1 is the group with the lowest probability of a ground ball, quartile 4 the highest. I also selected batters with 1000 plate appearances in that time frame. There were 243 batters in the study, also divided into quartiles on the same statistic.

Let's start with batting average. First here are the overall averages for the quartiles:

Remember, this study is looking at regulars on both sides of the ball, therefore we expect these groups to be better than average, hence the differences in batting average between batters and pitchers. Next, I pitted each pitcher quartile vs. each batter quartile. The 1-1 cell are pits pitchers and batters who tend to get lots of balls in the air vs. each other, while the 4-4 cell are pitchers and batters who keep the ball on the ground:

It looks like quartile two hitters (slightly fewer ground balls), are the best for generating hits, while the quartile 1 pitchers (fewer ground balls) are best for preventing hits. Maybe these type 2 hitters represent a more versatile group, one that can adjust to the type of pitcher on the mound.

Now let's take a look at slugging percentage. First the average for the quartiles:

Here, slugging percentage appears to have a lot more to do with the tendancies of the batter than the pitcher. Now let's look at quartile vs. quartile:

Again, slugging averages go down as you go from low grounder to high grounder batters. What's really fascinating is pitching quartile 3, which has the highest slugging percentages of all the pitchers in three of the four batting groups. Why is this?

It might be that this group are the ground ball pitchers who make mistakes. Bruce Hurst comes to mind. If he hung a pitch, it just got hammered. Pitching quartiles 1 & 2 are successful with balls in the air. Pitchers in quartile 4 don't hang pitches. But quartile three is where you find pitchers who make mistakes. I'll have to figure out what pitchers are in each quartile and see if that idea holds up.

Correction: Fixed the caption on the last table.