On Monday I touched on Tony Blengino’s presentation on contact management that he gave this past weekend at Saber Seminar in Boston. Tony measured the pitchers who were best able to manage contact by looking at HITf/x data, data to which us normal people have no access. But I theorized that something like sOPS+ (like ERA- but with OPS allowed) could be a replacement for the HITf/x data. I thought that sOPS+ might be able to tell us which guys are better at inducing weak contact and thus which guys can have an ERA that beats their ERA estimators.
When I say “tell us” I should clarify that could mean two different things. It’s the classic explanatory versus predictive problem. Yes, sOPS+ can explain why a pitcher’s ERA is lower than his ERA estimators in a given season, but, as it turns out, it can’t tell us whether he’ll be able to do so the next season. I spent some time last night looking at whether sOPS+ in year one correlated well with the gap between ERA and SIERA in year two. The answer is no. While the correlation was stronger than it was between ISO allowed (another weak contact indicator) and the ERA-SIERA gap, it was still far too small to be meaningful.
It’s obvious that things like sOPS+ and ISO allowed don’t stabilize quickly. And that should not come as a surprise given that we know certain batted ball data takes a long time to stabilize. That doesn’t mean it’s not a skill. It simply means you can’t look at any pitcher’s sOPS+ or ISO allowed in the offseason and rely on it too much in projecting them for the next season. But when I say you can’t look at “any” pitcher, I mean you can’t just look at any old pitcher. I do think there are some you can look at. Read the rest of this entry »