A fan of the Yankees, Red Sox, and large sample sizes.
WHEN HOMERUNS ARE HIT
Yesterday, John Lackey pitched a pretty good game, and hadn't surrendered any runs through 6 2/3 innings, at which point he was pulled in favor of Scot Shields after he loaded the bases. No problem, of course, since Brandon Inge was coming to the plate and Inge is one of the worst hitters in the American League (with apologies to Darin Erstad, Willie Harris, and quite a few others, actually). Of course, Inge proceeds to hit a grand slam, slamming Lackey with 3 ER. Still not a bad outing, and much better than Lackey's previous starts this year.
Tonight, Mulder hasn't been so hot, surrendering a bunch of hits and walks, before settling down and throwing a couple scoreless innings. He gave up a solo homerun to Jorge Posada, and was lucky Jorge didn't come to bat with men on base, like there had been most of the game. Mulder's outing would have been much worse had the HR come at a different time.
That got me thinking, are homeruns more likely to be hit at different game states? Most importantly, do more homeruns get hit without anyone on base? That makes a little sense - pitchers probably pay more attention to preventing homeruns when it will cost them more. Using Retrosheet data and ASS, here's a chart showing the probability of a homerun occuring at the different base states in the years 1972-1992 and 1999-2002:
basesit hr n hr/n
Here's just 1999-2002 data:
basesit hr n hr/n
Looks like homeruns get hit more often with the bases empty, and not as much with runners in scoring position. Of course, once the bases get loaded, the rate increases again, probably because the pitcher has to throw strikes, or risk walking in a run. Of course, the reason might also be that the pitchers who allow a lot of baserunners are bad, and bad pitchers also give up homeruns.
What about if we consider the number of outs? Does the number of outs alone affect when homeruns get hit? Using 1999-2002 data:
outs hr n hr/n
Hmm, a small advantage to the hitter with no outs. I don't know why, or if it's significant. I wonder if there are any unique combinations of base/out states that are extreme cases either for or against the hitting of homeruns:
outs:basesit hr n hr/n
Nothing crazy, but with no outs and the bases empty, homeruns occur at the highest rate. Those are the lead-off plate appearances (or plate appearances following lead-off homeruns), so maybe pitchers are just a little rusty or don't quite have their focus starting an inning.
If anyone's got any other explanations, let me know.
Comments: Post a Comment