The + is a minus

I've got plenty of reasons to not use ERA+ or OPS+. In a game so full of numerators and denominators, they're pretty quick ways to take already-flawed (and I mean merely flawed, not terminal) metrics and turn them into junk. It doesn't mean I don't understand why Sean Forman's babies are so beloved, and I've got no problem taking a gander.

There is one area of the ERA+ and OPS+ problem that I haven't seen anybody discuss lately, which is that BB-Ref used to not be an in-season resource. Now fans regularly peruse the current season's numbers, complete with ERA+ and OPS+ numbers. The park adjustments used for those are only current through 2007, and BB-Ref's park adjustments are pretty far from the state of the art at this point.

The 2008 Texas Rangers are treated as if they play in a neutral park. The 2008 Los Angeles Dodgers are treated as if they play in a fairly strong hitter's park. How have these teams and their opponents done offensively in these parks as opposed to away from them?

At The Ballpark: .290/.363/.477
Away: .277/.351/.436

At Dodgers Stadium: .243/.305/.359
Away: .268/.336/.409

No pseudo-record is being set this year by the Dodgers' relievers, because those park adjustments are eventually going to eat up the +'s when the 2008 numbers enter the bloodstream. The way I see it, James Loney has had a nice first full season, Kevin Millwood has been just as good as (if not better than) Hiroki Kuroda, and it is insane that Baseball Tonight was trying to hype up Angel Berroa this week (okay, that has nothing to do with this).

I'm not arguing for any particular approach to park factors, but at the very least there are several propagated on BB-Ref that simply don't reflect reality, and I'd rather leave them out of things.