Here’s the second graph from Jon T. Intern, plotting the Padres, Astros, Rays, Red Sox and Mariners. Why those teams? Mostly more randomness.

I picked the Padres and Mariners because of their reputations for having pitcher’s parks, the Astros because they have a stupid, ridiculous hill in center field, the Rays because they play on turf, and the Red Sox because of its peculiar dimensions.

Looks like more noise to me. The Padres are the first team here to have played to a negative home-field advantage, back in 2006: