from Amazon
Monday, September 24, 2007
WPA’s Cy Young
The same pitcher will have a different effectiveness as a starter or reliever. Essentially, as a starter, he’s pitching with one hand tied behind his back. You can’t just compare the relief stats to a starter without making an adjustment. And that adjustment is roughly .090 wins per game (or 9 innings, or .01 win per inning).
Therefore, when you look at WPA, add .01 win per inning as a starter, to compare to a reliever. The leaders in starter WPA (with IP in parens) are:
Peavy +5.0 (210 IP)
Carmona +4.4 (208)
Bedard +3.9 (182)
CC +3.5 (234)
Halladay +3.5 (218)
Beckett +3.3 (195)
Webb +3.1 (229)
With the starter/relief adjustment, Peavy comes in as +7.1 wins, Carmona is +6.5 wins, and so on. The leader among relievers is Putz at +5.7 wins. He’s in the conversation, but he’s not the standout his unadjusted stats have him at.
There are other adjustments to make, namely:
- park
- replacement level
- the Guy adjustment-leverage method
All of these will serve to knock Putz down a peg so that he’s just below the above list of starters, and no longer with them.
In the AL, you can make a reasonable claim for just about anyone.
Peavy is an odd case. His career ERA is 20% lower at home than on the road, pretty much reflecting the typical pitcher at Petco (i.e., we don’t think he has an extra discount or premium because of his park). But, he’s had 19 starts at home, 13 on the road, meaning he’s gotten an even more favorable setting than a pitcher at Petco. (It doesn’t matter that his 2007 road ERA is so much better… it simply means he sucked, relatively speaking, at home this year.) Even with the park advantage, Peavy is still the standout.