MLB Power Rankings: May 27th, 2015

With methods described in this post, here are the latest MLB power rankings!

TPI = Team Performance Index (my ranking metric).  Based on wRC, DRA, DRS, and UZR.
W% = Team Winning Percentage (i.e. real life)
Py% = Pythagorean Winning Percentage (based on real RS and RA)

On-Paper Playoff Leaders

American League - East: Rays, Central: Tigers, West: A's, Wild cards: Royals and Blue Jays
National League - East: Nationals, Central: Cardinals, West: Dodgers, Wild cards: Giants and Cubs

Notes

The Reds and White Sox were the big fallers this past week+ in terms of TPI, with both teams basically cratering.  I'm still pretty surprised at how bad the White Sox have been.  The Reds will hopefully rebound, a bit, but are still only a bit under their preseason projections.  Their decline this past week dropped them out of the TPI-based wild card, which now goes to the Cubs.  The Braves also faltered badly, although I like the Juan Uribe trade quite a lot for the Braves...short term, at least.

Meanwhile, the big risers were the Pirates.  They've been on a tear lately, climbing over .500 for the first time in a long time, and now just two games behind the Cubs.  It would be kind of neat to see those two teams ultimately claim the two NL wild cards, although the Giants certainly will have something to say about that.