Posted by admin on August 8, 2012
This question came up on the SABR-L newsgroup for SABR members.
I'm almost reluctant to ask this seemingly obvious question, but I'm puzzled:
What does Wins Above Replacement Value mean in terms of team success? Or put another way, if a team consists of nothing but replacement players, or -0- value WAR players, how many games does that theoretical team win? Surely not -0- games. Nor 81.
Here was my reply:
We have a pretty exhaustive intro to the metric here.
A replacement level team is set on our site to win 52 games in the year, so there are about 30*162 * (.500-.320) = 875 wins above replacement available for the league as a whole.
Here is an example conversion of WAR to team wins.
The Phillies batters have 9.8 WAR, pitchers 6.1 WAR, and they've played 110 games. A replacement team would win 110*.320 = 35.2 of those games. Using WAR, we estimate the Phillies to have 9.8 (WAR batting) + 6.1 (WAR pitching) + 35.2 = 51.1 wins compared to their 50 actual wins. 51.1 is right in between their actual 50 and their pythagorean 52 wins.
Using a team playing well, Texas has played 109 games, so the replacement team is at 109 * .320 = 34.9 wins. They have 13.7 batting WAR and 14.7 pitching WAR or an estimate of 34.9+13.7+14.7 = 63.3 wins. They actually have 64 with a pythag of 62.
Cumulative Team WAR is not constrained to match up with team wins and losses, but it definitely should match up to team wins and losses and team pythagorean wins and losses.