Player Evaluation: WARP, WS, TPR, etc.

[sweaver]

Since the other thread is evolving into a different discussion than what the name implies, a bit more information can be had here. There are three main (so far as I can tell) catch-all evaluation tools for baseball players, to wit:
Wins Against Replacement Player (WARP), done by Clay Davenport for Baseball Prospectus.
Win Shares, proposed by Bill James in the book of the same name.
Total Player Rating, calculated by Pete Palmer for Total Baseball.

To answer a question posed by TimmyB, the definition of the three levels of WARP, from the BP website...

WARP-1
Wins Above Replacement Player, level 1. The number of wins this player contributed, above what a replacement level hitter, fielder, and pitcher would have done, with adjustments only for within the season.

WARP-2
Wins Above Replacement Player, with difficulty added into the mix.

WARP-3
WARP-2, expanded to 162 games to compensate for shortened seasons. Initially, I was just going to use (162/season length) as the multiplier, but this seemed to overexpand the very short seasons of the 19th century. I settled on using (162/scheduled games) ** (2/3). So Ross Barnes' 7.4 wins in 1873, a 55 game season, only gets extended to 15.2 WARP, instead of a straight-line adjustment of 21.8.