THE BOOK--Playing The Percentages In Baseball

Monday, September 19, 2011

Is where you hit in the lineup conducive to better performance?

I’ve been meaning to do this study for a long time. 

All data from 1993-2010.  I also limit the data to players aged 25-29.  I ensure that a player is equally weighted in the two pools being compared (and that weight is the lesser of the plate appearances in the two lineup slots being compared).

(Imagine there’s three or seven paragraphs of a yapfest going on here.  I’m not going to do it.)

Ok, now, thanks for your patience in wading through all that.  Now onto the data.

There were 62,894 matching plate appearances for the leadoff slot and the #2 slot.  That is, I’ve got the same players represented in each of the two pools, and each are weighted appropriately.  Their wOBA in the leadoff slot is .332 and it’s .333 in the #2 slot.  That difference is less than one standard deviation.  In all cases, except two, the difference in the leadoff slot and the other 8 slots was less than one standard deviation.  And what are those two slots?

Players who hit leadoff and who hit cleanup: .352 in the leadoff and .368 as cleanup, which is 2.7 standard deviations.  And even bigger gap are those that hit leadoff and bat sixth: .334 leadoff and .344 batting sixth (3.3 standard deviations).

I did this for all the batting slot combinations.  Let’s take them one at a time.

Batting 2nd and everywhere else, except 3rd, shows less than 1 standard deviation of difference.  With with batting 3rd: .362 batting 2nd, .357 batting 3rd, 1.7 standard deviations.

Batting 3rd?  There’s the aforementioned batting 2nd, as well as batting sixth: .359 batting third, .354 batting sixth (2.3 standard deviations).

Batting cleanup?  That one has alot of differences.  None to match the leaoff, but also batting 4th/5th: .365 batting 4th, .362 batting 5th, 1.7 standard deviations.

Batting 5th?  In addition to the cleanup, we have these guys batting 9th as a gap.  Batting 5th, .335; batting 9th, .323; 2.4 standard deviations.

Batting 6th?  Many differences.  There’s the two already mentioned (leadoff, cleanup), and also batting 7th: .340 sixth, .337 seventh, 2.0 standard deviations.

Batting 7th?  There’s batting sixth, and also batting eighth: .321 seventh, .326 eighth, 2.8 standard deviations.

Batting 8th?  Only what was already mentioned with seventh.

Batting last?  Virtually across the board, batted slightly worse there than in all other batting slots.

If I take a simple average, this is what I get:

We see that hitting leadoff and batting ninth is “harder”, while batting cleanup confers some sort of advantage.  We’re not talking about a huge deal of course.  Up to a five point difference in wOBA (which translates to three runs over the course of a season).

We can come up with plausible scenarios as to the reasons.  By the time the pitcher gets to the ninth hitter, he’s been cruising a bit, but when he gets to the cleanup hitter, he’s a bit worn out.  Or, perhaps the reason that the batter was placed cleanup is because he actually was a bit better hitter that day, and he was placed ninth because he was a bit worse.  (Made me wish I would have controlled for platoon advantage too now that I think about it.) It’s possible there are other selection biases to account for.

Anyway, I quite enjoyed doing that, and if someone else likes it, great, welcome to my world.  This is what makes me go to bed after midnight.

All hail Retrosheet!  Now, off to fight that war for Oceania.