SIERA Watch: Day 3

Today, Tom Tango took a look at SIERAs treatment of walks. I'm really happy with the way the sabermetric community has so steadfastidly (?) prodded this new tool. It's very much a wiki-like reaction: in the first few days, everyone began tinkering with SIERA, opening the hood, poking the engine with a wrench (or whatever you do to cars). On the first day, I built a little Quick Calculator for the world to play with, and my dawg, FreeZorrilla, put it to the AL East test. Meanwhile, the big dogs at The Book blog put the metric through the rigors. The latest article produces some eyebrow-raising questions -- like: "Since when has allowing more walks been a good thing for pitchers?"

Anyway, Tango mentions the need for real-world comparisons to help gauge SIERA in non-isolation. So, let's take a closer look at our initial results:

On Tuesay, we found four "big" Cubs winners from the SIERA sweapstakes:

Esmailin Caridad: SIERA 3.08, xFIP 3.89 (19.1 IP)
Ted Lilly: 3.37, 3.98
Kevin Gregg: 3.66, 4.16
Carlos Marmol: 4.22, 5.16

(We'll ignore Caridad and his 19 and a third innings.)

So what about these pitchers make SIERA happy? First, let's review the two biggest goals of SIERA:

  1. Reward pitchers (who are unfairly punished by FIP) that have high SOs but also high HR rates.
  2. Reward pitchers (also punished by FIP) who walk alot, but induce a lot of GBs.
So, our illustrious three pitchers' profiles:

Lilly: Above average SOs (in the last 3 years), low BB% (also lately), and above average HRs (again, since becoming a Cub).
Gregg: Well above average K%, also kinda-high BB%, and ginormous HR rate (thus he lost his job as closer).
Marmol: Fly ball pitcher, above average K%, and "are you kidding me?!" (as in high) BB%.

The SIERA verdict?

Lilly: Win.
Gregg: Win.
Marmol: Huh?

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