Mailbag: Quality StartsBy
David asks: What do you think about QS % as an important measure of starting pitchers? Given the Yankees’ ability to score runs, and their strong bullpen, I’d place a high value on a pitcher’s ability to deliver quality starts, i.e., to be “consistently good.” On that basis we of course notice or confirm a number of things from 2011 AL pitchers with 140+ innings:
- CC Sabathia was of course consistently good at #10
- Michael Pineda was #8!
- A.J. Burnett‘s problems are NOT the occasional blow up; he’s consistently ineffective (worst in the league)
- Freddy Garcia wasn’t too far behind CC in consistency at #17
- Ivan Nova was middle of the pack at #27 (in the neighborhood of Gio Gonzalez, John Danks, Alexi Ogando, Phil Humber)
- Hiroki Kuroda was #14 in the NL, as a solid number two should be
I think that “quality starts” themselves are kinda silly, or at least the term “quality start” is silly. Three earned runs (why don’t we count unearned runs? they count on the scoreboard) in six innings is a 4.50 ERA, and that would have been a 116 ERA+ in 2011. If they changed the name of the stat to something like “decent start” or “winnable start,” them maybe it would be easier to swallow. That’s how I think of a quality start, it’s a winnable game for the Yankees with their offense and bullpen. My extension, QS% would just tell you how often a certain pitcher threw — not will throw — a decent or winnable game.
Quality starts are in no way predictive, they’re an output stat. They tell you the end result of the game without telling you how it happened. Did the pitcher throw eight innings of one-run ball with four hits, one walk, and nine strikeouts? Or six innings with three earned runs, two unearned runs, ten hits, three walks, and two strikeouts? In terms of quality starts, those two are the same thing. They’re kinda like the pitching version of RBI. We know the run came in, but we don’t know how it came in. Quality starts and RBI don’t tell us how likely the player is to do it again.
Like I said, I consider a quality start to be a winnable game for the Yankees, and that’s basically all I look for out of the back of the rotation, the Burnett’s and Hughes’ and Garcia’s in 2012. If the Yankees get a quality start out of those guys half the time, they’re well ahead of the fifth starter curve. I wouldn’t consider QS% to be a great measure of success or a high one percentage to be all that great without knowing more. It’s a great quick reference thing, but I have a tough time putting more stock into it, kinda like OPS. We have better metrics these days, but the old ones are still okay for a quick glance.