Introducing Pitching Independent Defense (Part 3)

We have been through two looks at something that I have dubbed “Pitching Independent Defense”, a quantitative look at defense from a team perspective, since I find player evaluation gets to be a little bit subjective. I am satisfied with the results of this evaluation and believe that it can be predictive of a pitching staff’s overall success.

I will say this, however. Early in the season, there is a lot of noise. While I believe the PID numbers are still instructive, they don’t correlate well with the difference between ERA and FIP like we found that it did over the course of 2012. This is fine, I think. The correlation between BABIP and DiffERA/FIP isn’t as strong at this point in the season either, and FIP was designed to take BABIP into account. Let’s not throw the baby out with the bathwater.

I believe PID is still a reliable tool for evaluating a team defense, but in this instance, I think the best way to prove it is by looking closely at the top 5 teams and the bottom team to make sure that real life events correlate with our findings. First, the top 5:

1) Giants
2) Rangers
3) Brewers
4) Braves
5) Orioles

The Giants and Rangers were in the middle of the pack last year and moved to the top of the list so far this year. Why might this be? Roster management, probably. The Giants upgraded at 2b and in the outfield on defense, while the Rangers went from Josh Hamilton to Leonys Martin and Craig Gentry in center field, one of the highest leverage positions on the field. Both teams, however, don’t fit the “better defense means better pitching” result, and at least in the Giants’ case, that is directly attributable to one of the league’s worst strand rates. That really is bad luck. The Rangers, on the other hand, are more of a mystery. We’ll call his inconclusive.

The Brewers fit everything much more conclusively. Jean Segura has been an excellent short stop. Corey Hart, a disaster in the outfield last year, was replaced by the much more stable Logan Schafer (et al) Their pitching has reaped the benefits from this point, and their ERA nearly matches their FIP, where it was .4 higher last year.

The Braves were strong last year on defense, as they are again this year with the addition of the Uptons. To be honest though, they mostly remained stable compared to where they checked in last year. This is a team whose pitching staff is seeing a lower ERA than FIP.

Rounding out the top 5 were the Orioles, who have had an ineffective pitching staff, but a strong defense. This goes all the way back to last year, with great gloves like Nick Markakis and Adam Jones in the outfield and JJ Hardy in the infield. They moved up in the rankings so far this year thanks in large part to adding Nate McLouth, formerly a centerfielder, in left, and replacing sieve Mark Reynolds with stud Manny Machado.

At the bottom of the PID rankings, edging out last year’s bottom feeders (the Astros), are, unfortunately, the Twins. This does make a world of sense, however. Last year, they had one of the best outfields in the land, with both Ben Revere AND Denard Span ranging the field, and now they have played a catcher and a first baseman in right and a rookie in center. In the infield, they seem committed to Trevor Plouffe. It’s not optimal, and it has hurt in the ERA department.

But just a little bit. If anything, this makes one wonder how much team defense helps a team or not. Over the course of a season, a good defense can save as much as .25 runs a game, which is enormous, but it takes an entire season to bear that out.

I hope this little series has been informative, and if you have any input, if you would like to help out with some updates to the formula, I would love to hear them. Before I wrap it up, I thought I would spell out the formula one more time.
100((.8677*LD%+.1121)-BABIP)+3 = Raw PID.
RawPID*Fielding% = Total PID