Monday, June 2, 2014

The Astros in May 2014: Starting Pitchers and Advanced Metrics.

In follow up to the earlier article, which involved going through the box scores of the Astros, Angels and White Sox games for the month of May, below are the per-start raw metrics for the three teams' starting rotation for the month of May.  These are averaged, and therefore potentially what could be expected on a per-start basis:

Houston Astros
IP: 6.27, H: 6.07, R: 2.76, ER: 2.41, BB: 1.79, K: 4.86, HR: 0.48,
Ground Balls: 8.62, Fly Balls: 5.14.
Game Score: 53.7.

Chicago White Sox
IP: 5.59, H: 6.11, R: 3.22, ER: 2.96, BB: 1.96, K: 4.26, HR: 0.77,
Ground Balls: 6.44, Fly Balls: 5.63.
Game Score: 47.4.

Los Angeles Angels of Anaheim 
IP: 6.25, H: 5.54, R: 2.96, ER: 2.68, BB: 2.07, K: 5.21, HR: 0.57,
Ground Balls: 7.03, Fly Balls: 6.32.
Game Score: 54.4.

The Astros' 0.2 R/ER difference over the Angels, and their 0.5 R/ER difference over the White Sox (and remember, this is per start, so the Sox are giving up more runs in fewer innings) is the most striking feature of the above results.  The more you dig, the more interesting this is.

Advanced metrics, as per Fangraphs, presented as a staff, but weighted for innings pitched, rather than averaged, Astros only:

Houston Astros
ERA- : 84.5
FIP- : 92.0
xFIP- : 92.9
FIP :  3.45
xFIP :  3.59
SEIRA :  3.62

(Remember that the Astros' ERA for May was 3.45)

Remember that ERA-, FIP- and xFIP- are all measured against 100, meaning that the Astros starters were better than league average pitching in all three measures - in the case of ERA-, they were 15.5% better than the league average,

FIP, xFIP and SEIRA are all designed to be measured in a similar way to ERA.  In this article on FIP, the FIP would be ranked between "Great" and "Above Average" on the explanatory table.  Remember, this is as a staff, so is a summation of all the pitchers together, weighted for innings pitched.  SEIRA is the most unfavourable toward the Astros starters, likely because of their high ground ball rates (on the premise that the ground balls go for hits more often than flyballs).  But, the Astros shift like crazy, and perhaps that makes a difference in having an ERA lower than SEIRA.  Be interesting to watch.

Digging deeper, it would be nice if some of these numbers were put into some context, however.  Lets try and find a pitcher from 2013 who has an ERA and advanced metrics closest to those above.

2013 Derek Holland had an ERA of 3.42, and FIP of 3.44, and xFIP of 3.68.  SEIRA was 3.74.  His ERA- was 81, and his FIP- was 82.  Not the worst match in the world.  Holland was worth 4.8 WAR for the 2013 season (he threw 213 innings), and was ranked 11th in baseball WAR.

The Astros May staff, as a population or group, is very similar to 2013 Derek Holland.  The 11th ranked pitcher in baseball.

And this is as far and I am going to dig (and the most interesting nugget of all): the Astros starters can be summed up (and compared with the Angels and the White Sox) by one single number.

Astros Starting Pitching WAR: 3.2.

The Angels' WAR: 3.0

The White Sox WAR: 1.6

Top AL score for starting pitching in May??

The Astros' 3.2.  Second is the Yankee starters' 3.1 WAR.

Can't wait for June.  Or, having read Cockroach's game recap, can't wait for June 2nd, more precisely.


1 comment:

Anonymous said...

Wow. Leading AL in War in May. Wow