Purgatory Online

Thursday, November 07, 2002

Matt Szefc makes the case for Barry Zito as AL Cy Young. This one's weird: Szefc argues that, because Zito pitched more games against over-.500 opponents, he should get the nod over Pedro Martinez. But then he presents numbers demonstrating that Zito was substantially worse against those opponents than Martinez (Zito 18 starts, 3.66 ERA; Martinez 13 starts, 2.14 ERA). Zito is clearly the beneficiary of starts against bad teams here. Granted, he had five more starts in which to be roughed up by good teams, but Martinez's ERA against good teams was actually slightly better than his ERA against the sub-.500s. I think that's kind of a wash, then - sure, Martinez might have had worse numbers if he's pitched the same schedule, but there's absolutely no evidence for it.

Lowe, meanwhile, does show a benefit from pitching against weaker teams. Given that his ERA and IPs are very similar to Zito's, and his strikeouts are substantially less (and yes, okay, I admit strikeouts should be a factor too since they're the only form of out that the pitcher gets unassisted by his defense), I can't see voting for Lowe over Zito.

So it comes down to Zito or Martinez. Zito's ERA was 2.75, about 22% worse than Martinez's 2.26. Zito's IPs, however, were 229.1, 15% more than Martinez's 199.1. Martinez had a 31% edge in strikeouts, 239-182. The question is, how do we weigh these? Would you rather have a guy who pitches very well for a little longer, or a guy who pitches brilliantly for a little less?

It's very close. Durability is important because it provides consistency and doesn't require much juggling from the manager. But let's say Zito pitched well enough to win an expected 20 games in 230 innings, while Martinez pitched well enough to win an expected 20 games in 200, then broke down and had to be replaced with the biggest scrub in the bullpen, who threw the next thirty innings with a 7.50 ERA. You've got to figure that there's at least some chance that, during that stretch, the Red Sox will pick up a win or two, right? So after 230 innings, the Red Sox would actually be +1 or +2 compared to the A's.

The problem is applying this to the current question. I don't know if I've ever seen a study correlating ERA to expected wins, although I'm sure one exists. I don't have time at the moment to look for it, but I will in the next few days. I suspect, however, that when all the math is done, Martinez's 22% advantage in ERA outweighs Zito's 15% advantage in innings pitched, or, at the very least, it's close enough that Martinez's higher strikeout total would provide the tiebreaker. So, if I had a vote, I'd...well, I'd have thought about it in time to do the math. Provisionally, though, I'd say Martinez.

You won't hear me complain if they pick Zito, though, and I expect they probably will based on durability, his performance over the past two years, and his team making the playoffs.