Unless you’ve been living under a rock, you’re aware that there has been a ton of discussion online lately about the AL MVP vote and the discussion took an unexpected turn when Bill James got involved and attacked the utilization of the various WAR metrics.
Baseball-Reference.com’s Sean Forman has been responding to James and throughout it all, Sean has taken the high road and displayed his usual restraint. He’s also collected a bunch of links related to the discussion that are well worth checking out. You can see those here:
This comes from the Baseball Prospectus piece that Sean linked:
Back-fitting a team’s actual wins to a player’s value, as James suggests, repackages the same problem in a different form: we still have hitters who get on base but don’t get driven in, or pitchers who keep the ball on the ground but have poor fielders behind them, and we then have to decide how to fairly adjust for those situations.
In fact, James built his career upon observing and skewering such incongruities, so it seems rather strange for him to criticize a more statistically reasonable approach—using the grand mean value of a run to the entire league—as opposed to the noisier estimate of what a run ended up meaning to a particular team (and even then, still only the average value to that particular team). The fact that a player’s value is not fully realized does not mean that player has no unrealized value. Put another way, even if Reds hitters struck out to complete every inning in which Joey Votto drew a walk, it seems odd to claim that those walks were that much less worth doing.
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Sticking with Baseball Reference, we can correlate team WAR (batting and pitching combined) with winning percentage, and the correlation is .93,3 which means that bWAR accounts for about 87 percent of all run scoring and prevention in baseball. That’s pretty darn good, and not atypical for the various WAR systems. Does that leave 13 percent of what happens on a baseball field unaccounted for? It sure does. But again, so what? WAR doesn’t pretend this variance does not exist; it merely refuses to punish individual players for the inherent volatility we enjoy seeing in the game. And while there are those who enjoy complaining about WAR for this reason, my sense is that many of these people would complain about WAR regardless.
Source: Jonathan Judge, Baseball Prospectus