Re-WERCing Things

Linear Weights guru Tom Tango likes to use wOBA against for pitchers as well as hitters.  However, he told me yesterday that Base Runs is preferable to trying to convert wOBA to runs as I did in my last post.  So, I'm going to do some leader boards according to Base Runs today.  It turns out they aren't radically different from the linear weights leaders presented my previous post, although linear weights seemed to inflate the value of star pitchers (runs saved above average) a little bit

The Base Runs measure was created by David Smythe in the early 1990s.  It is based on the idea that we can estimate team runs scored if we know the number of base runners, total bases, home runs and the typical score rate (the score rate is the percentage of base runners that score on average.  Base Runs also works well for individual pitchers.  The complete formula can be found here.

Justin Verlander has 39 Base Runs Against in 151 innings so far this year.  This means that he should have allowed an estimated 39 runs based on the number of base runners, total bases and home runs he has allowed.  He has allowed 39 actual runs, so runs are scoring against him at the exact rate you would expect.

Verlander has allowed 33 Base Runs Above Average (RAA) which means that he has saved the Tigers an estimated 33 runs compared to the average pitcher in the same number of innings.  Table 1 shows that he is tied for first in the American League with Angels ace Jered Weaver.


Table 1 - AL Base Runs Allowed Above Average Leaders as of July 10

Player	Team	IP	Base Runs Against	RAA
Jered Weaver	LAA	140.1	33	33
Justin Verlander	DET	151.0	39	33
Josh Beckett	BOS	111.0	27	25
James Shields	TBR	142.2	44	24
Dan Haren	LAA	134.1	40	24
CC Sabathia*	NYY	145.2	47	22
Felix Hernandez	SEA	144.0	49	19
Michael Pineda	SEA	113.0	35	18
Philip Humber	CHW	107.1	34	17
Alexi Ogando	TEX	104.2	33	16

Table 2 shows that Verlander has allowed 2.32 Base Runs per nine innings.  About 93% of runs are earned, so multiply this result by .93. to put it on the same scale as ERA. The final result is a weighted component ERA.  Although, I am no longer using linear weights here, I'll keep calling it WERC because others have said the like the name. It's really not a novel idea though.  U.S. Patriot of Walk Like a Saber has been using Base Runs to evaluate pitchers for a while but prefers to not convert to the ERA scale.

Getting back to the example, Verlander has a 2.16 WERC.  Since his Base Runs Allowed is the same as his actual runs allowed, this is almost the same as his real ERA.  He is third in the league behind Weaver (1.98) and Josh Beckett of the Red Sox (2.06). 


Table 2: AL WERC Leaders as of July 10

Player	Team	IP	Base Runs/9 IP	WERC
Jered Weaver	LAA	140.1	2.13	1.98
Josh Beckett	BOS	111.0	2.21	2.06
Justin Verlander	DET	151.0	2.32	2.16
Dan Haren	LAA	134.1	2.68	2.49
James Shields	TBR	142.2	2.77	2.58
Michael Pineda	SEA	113.0	2.83	2.63
Philip Humber	CHW	107.1	2.87	2.67
Alexi Ogando	TEX	104.2	2.89	2.68
CC Sabathia*	NYY	145.2	2.92	2.72
Felix Hernandez	SEA	144.0	3.09	2.87

The raw data used to create the statistics in this post was extracted from Baseball-Reference.

Coke Joins Rotation for Real

In the first big news of the Tigers "off-season", Jim Leyland announced that Phil Coke will join the starting rotation next year.  The 27-year-old southpaw will get his first start for the Tigers today  but that's because because none of their regular starters are available.  He is not expected to pitch more than two or three innings this time.  Next year, the plan is for him to be a full-time starter. 

Coke will be the sole lefty in the rotation behind Justin Verlander, Max Scherzer and Rick Porcello.  Armando Galarraga is the leading contender for the fift spot.  The move indicates two things.  First, Jeremy Bonderman is not likely to be back next year which is not a surprise.  It also suggests that they probably won't pursue a starting pitcher during the off-season.  Instead, we can expect them to focus on hitters and relievers.    

Strong First Start for Porcello

The one thing the Tigers need more than anything if they are going to remain in contention all year is for Rick Porcello to turn his season around.  He was sent down to the minors in June after posting a 6.14 ERA in 13 starts.  After four starts in Toledo, the hope is that he'll respond to his triple-A stint anywhere close to as well as Max Scherzer has.  Scherzer has a 2.86 ERA and 11 strikeouts per nine innings since returning from a two-game trip to Toledo.

Porcello returned to the Tigers rotation with a bang tonight.  He threw eight innings of six-hit one-run ball versus the Indians in the second game of a doubleheader.  His control was outstanding as he threw 71 of his 99 pitches for balls and walked nobody. 

He had his sinker working well enough to put up an 11/6 gound out fly out ratio.  prior to his demotion, he had a 28/38 GO/FO ratio which isn't going to work for a sinker ball pitcher.  In addition to the ground balls, he also had a season high six strikeouts.

Some will say that it's only game against a weak hitting Cleveland Indians club and they are correct.  However, this is the same team against which Max Scherzer and Justin Verlander have struggled the last two days.  The important thing is that Porcello was throwing strikes and inducing grounders, two things he wasn't doing so much earlier in the year.           

What's Wrong with Porcello?

The Tigers were routed by the White Sox 15-3 tonight and Rick Porcello was the victim again.  Porcello got through the first three innings allowing just one run but completely fell apart in the fourth as the White Sox scored seven runs.  In all, Porcello allowed eight runs on eight hits and not many of the hits were cheap ones.  The damage included two home runs, two doubles and and some hard hit singles. 

Porcello has now seen his ERA rise from 3.96 in his rookie year to 6.09 this year.  His peripheral stats have regressed across the board from 2009 to 2010.  His ground ball rate has plummeted from an American League leading 54.2% in 2009 to 48.9% this year.  His strikeout rate which was already low at 4.7 per nine innings last year is down to 4.0 this year.  His walk rate per nine innings has increased from 2.7 to 3.1. 

Opinions vary on the reasons for his problems but there is a consensus on a couple of points.  His sinking fastball is not working this year like it did last year.  He seems to be getting it up in the zone more often, which is the likely reason for the decrease in ground ball rate.  According to FanGraphs, he was 16.1 runs better than average with his fastball last year.  This year, he was 3.1 worse than average before today's disaster.

Beyond his fastball, the 21-year-old right-hander doesn't have any plus pitches as of yet.  Both his breaking pitch and change-up need work.  So, when he has trouble locating his fastball, he's not an effective pitcher.

It's way too early to panic about the career of a pitcher as young as Porcello.  But what about this year?  Is it time for the Tigers to send him to Toledo to refine his game?  They sent Max Scherzer down a few weeks back and he has come back with better stuff just two weeks later.  I'm think that Porcello could be next.