Opening Day's correlation of salary rank to power rank was an ok (but I still wouldn't bet on it) 0.59.
I updated the power rank numbers during the All Star Break, resulting in a new correlation of 0.31.
We could call the difference in coefficient from Opening Day to now the Cardinals-Pirates-Rays-Athletics effect. These teams are getting awesome production out of relatively cheap rosters. Alternately, we could call the difference Dodgers-Giants-Angels effect. Those teams are both abysmal and expensive.
Does anyone know who is tracking the effect trades are having on annual salaries by team?