A fan of the Yankees, Red Sox, and large sample sizes.

 
I've been playing around with a spreadsheet to compute expected ERAs based on DIPS, and wondered exactly how much effect fielding actually has. Taking a league average pitching staff ($BB=.90, $SO=.182, $HR=.37), I computed Xtrapolated ERA for a range of $H values around the MLB mean of .287. Here are the results:

 $H  XERA

.267 4.97

.277 4.75

.287 4.55

.297 4.34

.307 4.15

So it looks like the difference between league average fielding and typical best/worst fielding is .4 runs per game. Over an entire season, that's a difference of 65 runs. Definitely not chump change. The difference between the best and worst fielding teams is about 130 runs. Maybe there is something to defense winning championships. The next step is see how much of effect a good pitching staff makes over a league average pitching staff. My guess is .9 runs per game, thus making defense, on average, 70% pitching and 30% fielding.

Posted by Sky at 3:51 PM | 0 comments