Tuesday, February 6, 2007

Johan Santana
Johan Santana had the Cy Young award snatched
from him by Bartolo Colon because of the
overvaluing of the win statistic.

There is nothing quite like baseball in that its statstics are heralded more so than the games themselves. Homerun chases, potential Triple Crown winners, career strikeouts -- they're all statistics baseball fans adore and pay attention to. Some statistics are meaningful and are good metrics of a player's performance, while others are simply window dressing and not indicative of a good or bad player.

One of those metrics is the win. Simply put, a win is given to the pitcher of record when the team took its final lead. There is no limit on how many runs a pitcher can give up to earn a win, and there is no limit on how many runs an offense can score in support of the pitcher that earns the win. Pitcher A can pitch 9 innings and give up just one run and not be credited with a win (because his team scores one or less runs) while Pitcher B can pitch 5 innings, give up 15 runs, and still earn the win if his team scores 16. On the basis of wins, both pitchers came out the same, but clearly Pitcher A put forth the better effort.

Over the course of a season, the win is a poor metric to judge a pitcher's worth. For example, Minnesota Twins left-hander Johan Santana lost the 2005 AL Cy Young Award to Bartolo Colon of the Los Angeles Angels of Anaheim, even though Santana led or tied Colon in every statistical category except for wins (five less than Colon) and walks (two more than Colon); Santana had less losses (1), more complete games (1), more shutouts (2), more innings pitched (9), less hits allowed (35), less earned runs allowed (16), less homeruns allowed (4), more strikeouts (81), a lower ERA (0.61), a lower WHIP (0.19), and a lower batting average against (.044) (Chart). Add in the fact that Santana's Twins scored him 4.47 runs per game on average, while Colon's team scored him 5.55 runs on average, and Santana clearly was the better pitcher in 2005.

Another example that shows the futility of the win is comparing two seasons where a pitcher got the same amount of wins. For this example, we will compare the 1998 and 2006 seasons of Steve Trachsel, of the Cubs and Mets, respectively. In 1998, Trachsel started 3 more games, pitched more innings (43 and two-thirds), struck out more hitters (70), had a lower ERA (0.51), had a lower WHIP (0.22), and a lower batting average against (0.03). In 2006, Trachsel gave up less hits (19), less earned runs (12), less homeruns (4), and less walks (6), but in three less games (Chart). If he were to pitch those three games, he would have to allow an average of 6 hits, 4 runs, 1 homerun, and 2 walks or fewer per game. Clearly, Trachsel's 1998 season was better than his 2006 season, but he got the same amount of wins, and nearly identical run support (5.23 in '98 and 5.46 in '06), in both.

So, what should be used in lieu of the pitching records? Sabermetricians offer a wide array of ways to evaluate a player's worth. Here are some:

Other statistics that are poor metrics: