Baseball Strategy:What is DIPS, anyway?

A Lot Of What We Call “Good Pitching” Is Actually Good Defense.

In 2000, a paralegal named Voros McCracken discovered that pitchers had real control over only three things: the number of walks allowed, the number of home runs allowed, and the number of strikeouts recorded. That’s crazy talk, though, right? Well, a bunch of guys even geekier than Voros tried to prove that he was nuts, or bad at math, or something... but they couldn’t. All they could find is that, on top of walks, homers, and strikeouts, pitchers can consistently control whether they give up fly balls or ground balls; and, to a degree, how many extra-base hits they allow. But -- other than some knuckleballers -- they don’t seem to be able to control with any consistency how many hits they give up when the ball is put into play. Which is to say that defense is of paramount importance to baseball. Think about it: once a pitcher gives up contact and the ball is fair, everything that happens depends on the fielders behind him -- good glovemen can make him look really good by getting to balls that normal players wouldn’t, but bad ones can inflate his ERA in a hurry (not through errors, mind you, but by lacking the range to even be in a position to commit an error). In other words, just like a lot of batting average was pure chance, a lot of pitching is luck as well. The numbers bear this out as well: ERA is one of the least consistent statistics in baseball from year to year, meaning that a lot of the variance is due to randomness and not actual skill. Some stats try to strip away luck by focusing just on groundball-flyball ratio, walks, homers, and strikeouts; these are generally called “Defense-Independent” pitching stats (DIPS), and they actually predict a player’s ERA the next season better than ERA itself. Anyway, the next time you see a bloop single fall in, don’t blame the pitcher. Blame lady luck.