Those who read AN know that one of my pet peeves is the notion that all stretches of unusually high BABIP (batting average on balls put in play) automatically reflect "good luck," while all stretches of unusually low BABIP must reflect "bad luck." Yet certainly the smaller the sample, the better chance that a freakishly high or low BABIP is little more than statistical noise -- after all, a flurry of "at 'em balls" or a cluster of badly hit balls that roll, bloop, and chop their way to base hit glory, is hardly unheard of.
A hitter's BABIP usually hovers somewhere between .280-.320. So when you see that a hitter who is having a bad season has a BABIP of .240, how do you know whether this is predominantly due to chance factors that will self-correct or whether the hitter is actually contributing, non-randomly, to his poor performance? Does Rajai Davis deserve credit for his excellent hitting line this year -- which includes an exceptional BABIP -- or has a cluster of lucky bounces and fortunate placement just made his hitting look better than it has actually been?
I have a couple theories that can be checked by those adept at unearthing the statistical data. I'm not suggesting the theories are accurate; I am putting them out there as "common sense" ideas, and asking readers to feel free to reveal that they are sensible or perhaps dead wrong...
It seems to me that two factors should influence "expected BABIP": One is putting balls into play on favorable counts, and the other is putting "strikes" into play.
I would imagine that when 3-1 pitches are put into play, the average BABIP is higher than when 0-2 pitches are put into play, that the average BABIP "following a 2-1 count" is higher than the average BABIP "following a 1-2 count," and so on. So if a hitter is generally getting into, and hitting from, favorable counts, I would expect a low BABIP to self-correct (a more "external locus of control") more than if I found that the hitter was getting into, and hitting from, unfavorable counts -- where a lower BABIP should be expected and the hitter is more responsible for his lack of success (a more "internal locus of control").
Similarly, I would imagine that hitters (at least those not named Vlad or Panda) do better when the ball they put in play is a strike as compared to when it is, say, a sinker below the knees or a fastball running in on the hands. So if a hitter with a high BABIP is also putting "strikes" in play at a higher than average rate, I would be less inclined to assume it to be luck and more inclined to give due credit for the stretch of success.
You get the idea. I'm just wondering whether in addition to "line drive %," two good stats to check to help separate "luck/chance" from "skill/earned" might be to look at how the counts that B's are being PIP compare to league averages, and to look at how the percentage of "putting strikes into play" compares to league average.
Note: If you haven't seen this post about the upcoming Community Service (9/19) and Chez Nico (9/29) gets-together, check it out and reply accordingly if you want to be a part of one or both!