[QUOTE=Jackknifed Juggernaut]
Maybe I’m missing something, but isn’t the point of Adjusted OPS+ to determine who truly is the better overall hitter?
Let’s assume that MLB is comprised of an equal number of lefties and righties, with equivalent aggregate OPS’s. Now, if you reversed the dimensions of Yankee Stadium (mirror image of what it is today), Rodriguez would clearly have a higher slugging % and probably a higher on-base %, while the ballpark adjustment to OPS would stay the same. This would move him higher up on the all-time list.
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But Yankee Stadium isn’t built that way. It’s built the way it is.
The word “punishes.” OPS+ measures the value that a player actually had relative to his peers, not the value he WOULD have had had he played elsewhere, or if Yankee Stadium had been designed differently.
As Gadarene points out, you can speculate that Rodriguez might have better stats if he’d played in a different sort of park. Knowing that righthanders have a slight disadvantage in the Bronx is useful to know for future reference - if, for example, a righthanded fly ball hitter were to move from Yankee to Fenway. But in terms of determining A-Rod’s actual performance to date, his OPS+ is an accurate picture of the value of those facets of his offense.
That Yankee Stadium might push his career OPS+ down (by one point, maybe) might strike you as being unfair, but it’s a real picture of what his relative value has been.
The purpose of park effects is to adjust away illusions that affect everybody. If the league batting average is .270, but Great American Ballpark raises batting average by 10 points, a player who hits .280 is just keeping up with what everyone else in the league is doing; the 10 points have no value, they’re park effect. But if there’s something about a player that prevents him from taking advantage of that and he doesn’t get than 10-point boost, that reduces his value. It might not be fair; it might go away if he signs with Chicago. But it still reduces his value by the equivalent of 10 points of batting average, whatever that is (it’s not a lot.)
So it is with A-Rod. Maybe Yankee Stadium costs him a few homers a year. If it costs EVERYONE a few homers a year, then his OPS+ will reflect that. If it costs A-Rod a few more homers than the league average, his OPS+ will go down a little, but that’s simply a reflection of his real value.
And as I said, the effect of this is pretty small anyway. Yankee’s not as bad as it used to be, and A-Rod has only played there for about a third of his career. If you were to assume that he lost four homers a year every year he’s played there, that landed as fly outs - which is a lot, really - the effect on his OPS+, if I’m doing the math right, is just one point. You’re going to have a lot of difficulty building a convincing case that Yankee Stadium hurts him to any greater degree than that, because
- He has, in fact, hit just as well in New York as he has on the road - in fact, this year he’s one of the most extreme HOME hitters in baseball, and
- His two best OPS+ years have been in a Yankee uniform, and this year he’s on a pace to have his third best.
It is interesting to note than Frank Thomas, in his first eight years in the majors, put up a better OPS+ every year than any season A-Rod had ever had prior to joining the Yankees.
