The limitations of all three measures have been discussed here before. Win-loss record is a team statistic heavily influenced by run support and is generally not a good way to evaluate individual pitchers. The ERA statistic is better but also has shortcomings such as:
- ERA gives pitchers full credit/blame for results of batted balls in play despite the fact that they share that responsibility with fielders. For example, a pitcher with a strong defense behind him will tend to give up fewer hits (and thus fewer runs) than if he has a poor defense behind him.
- ERA gives pitchers full responsibility for sequencing or timing of events, that is, it assumes that they can control when they give up hits and walks. For example, if a pitcher pitches extraordinarily well with runners in scoring position in a given year, he will have a lower ERA than if he had a typical year in those situations. Additionally, a pitcher who tends to bunch base runners together in single innings will have a higher ERA than if he had a typical year distributing base runners more evenly.
Because they are based on things that pitchers essentially control, the DIPS metrics are said to be better measures of true talent than ERA. As a result, they are also better than ERA at predicting future performance. However, they only measure a portion of a pitcher's talent and should be used as complements to ERA rather than as replacements.
It is not known exactly how much control pitchers have on the results of balls in play, but recent research tells us that some pitchers are better than others at preventing hits on balls in play. For example, Mike Fast, formerly of Baseball Prospectus and now a MLB sabermetrician, used Sportsvision's hit f/x data to show how pitchers varied on the speed of balls off the bat.
So, rather than making the big leap from ERA to FIP, it might be a good idea meet half way. Instead of removing hit prevention and sequencing in one step, it might be better to remove one factor at a time. Bill James did that with his Component ERA (ERC). Applying the runs created methodology to pitchers, he determined what a pitcher's ERA should have been based on walks, hit batsmen, strikeouts, homers AND hits allowed. I'm going to look at some similar statistics here based on more modern measures such as linear weights and Base Runs.
We often use Weighted On-Base Average (wOBA) to measure overall hitting performance and it can also be used for pitchers. The American League wOBA Against (wOBAA) leaders are shown in Table 1 below. Clay Buchholz of the Red Sox currently leads the league with a .242 wOBAA. Scherzer is third in the league at 254. Another Tiger among the leader is Anibal Sanchez who is fifth at .269
Table 1: AL wOBA Against Leaders
Team
|
G
|
IP
|
wOBAA
|
|
Clay
Buchholz
|
BOS
|
12
|
84.1
|
.242
|
Chris
Sale*
|
CHW
|
16
|
113.1
|
.251
|
Max
Scherzer
|
DET
|
17
|
116.2
|
.254
|
Hisashi
Iwakuma
|
SEA
|
18
|
121.1
|
.261
|
Anibal
Sanchez
|
DET
|
14
|
86.2
|
.269
|
Yu
Darvish
|
TEX
|
18
|
119.1
|
.270
|
Hiroki
Kuroda
|
NYY
|
17
|
106.2
|
.278
|
Bartolo
Colon
|
OAK
|
17
|
113.1
|
.281
|
Ervin
Santana
|
KCR
|
17
|
118.0
|
.282
|
Alex
Cobb
|
TBR
|
13
|
83.2
|
.283
|
Felix
Hernandez
|
SEA
|
18
|
123.2
|
.287
|
Justin
Masterson
|
CLE
|
19
|
128.2
|
.288
|
Jose
Quintana*
|
CHW
|
17
|
100.0
|
.292
|
A.J.
Griffin
|
OAK
|
17
|
109.1
|
.293
|
James
Shields
|
KCR
|
18
|
122.2
|
.295
|
It's generally a good idea to convert to runs allowed when trying to evaluate pitchers and this can be done with the Base Runs measure created by David Smyth in the early 1990s. The Base Runs metric 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.
Table 2 shows that Scherzer has 35 Base Runs Against in 116 2/3 innings so far this year. This means that he should have allowed an estimated 35 runs based on the number of base runners, total bases and home runs he has allowed. He has allowed 41 actual runs, so runs are scoring against him at a higher rate than you would expect. That could possibly be due to poor defense (which wouldn't be surprising for the Tigers), unfortunate timing or just bad luck on locations of batted balls.
Scherzer has 22 Base Runs Above Average (RAA) which means that he has saved the Tigers an estimated 22 runs compared to the average pitcher in the same number of innings. Table 2 shows that he is second in the league on that metric. White Sox southpaw Chris Sale leads the league with 23 RAA. Sanchez is eighth with 13 RAA. Doug Fister is listed at 12 RAA, but that does not include today's outing.
Table 2: AL Runs Saved Leaders
Player
|
Team
|
G
|
IP
|
Base
Runs
|
RAA
|
Chris
Sale*
|
CHW
|
16
|
113.1
|
32
|
23
|
Max
Scherzer
|
DET
|
17
|
116.2
|
35
|
22
|
Clay
Buchholz
|
BOS
|
12
|
84.1
|
21
|
20
|
Hisashi
Iwakuma
|
SEA
|
18
|
121.1
|
40
|
19
|
Yu
Darvish
|
TEX
|
18
|
119.1
|
42
|
16
|
Justin
Masterson
|
CLE
|
19
|
128.2
|
46
|
16
|
Bartolo
Colon
|
OAK
|
17
|
113.1
|
40
|
15
|
Anibal
Sanchez
|
DET
|
14
|
86.2
|
29
|
13
|
Ervin
Santana
|
KCR
|
17
|
118.0
|
45
|
13
|
Felix
Hernandez
|
SEA
|
18
|
123.2
|
47
|
13
|
Hiroki
Kuroda
|
NYY
|
17
|
106.2
|
39
|
13
|
Doug
Fister
|
DET
|
17
|
109.0
|
41
|
12
|
James
Shields
|
KCR
|
18
|
122.2
|
49
|
11
|
Derek
Holland*
|
TEX
|
17
|
112.0
|
45
|
9
|
Alex
Cobb
|
TBR
|
13
|
83.2
|
32
|
8
|
Data source: Baseball-Reference.com
Finally, Table 3 shows that Scherzer has allowed 2.52 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 not using linear weights here, I call it WERC because others have said they like the name. It's really not a novel idea though. 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, Scherzer has a 2.52 WERC which places him third in the league behind Buchholz (2.08) and Sale (2.36). Because Scherzer's FIP and WERC are so similar, the discrepancy between ERA and FIP would appear to be the result of sequencing rather than batted balls. So, if there is any bad luck involved, it's probably timing.
Table 3: AL WERC Leaders
Player
|
Team
|
G
|
IP
|
Base
Runs/9 IP
|
WERC
|
Clay
Buchholz
|
BOS
|
12
|
84.1
|
2.24
|
2.08
|
Chris
Sale*
|
CHW
|
16
|
113.1
|
2.54
|
2.36
|
Max
Scherzer
|
DET
|
17
|
116.2
|
2.71
|
2.52
|
Hisashi
Iwakuma
|
SEA
|
18
|
121.1
|
2.98
|
2.77
|
Anibal
Sanchez
|
DET
|
14
|
86.2
|
3.02
|
2.80
|
Yu
Darvish
|
TEX
|
18
|
119.1
|
3.16
|
2.94
|
Bartolo
Colon
|
OAK
|
17
|
113.1
|
3.22
|
2.99
|
Justin
Masterson
|
CLE
|
19
|
128.2
|
3.26
|
3.03
|
Hiroki
Kuroda
|
NYY
|
17
|
106.2
|
3.31
|
3.08
|
Ervin
Santana
|
KCR
|
17
|
118.0
|
3.40
|
3.16
|
Doug
Fister
|
DET
|
17
|
109.0
|
3.40
|
3.16
|
Felix
Hernandez
|
SEA
|
18
|
123.2
|
3.45
|
3.21
|
Alex
Cobb
|
TBR
|
13
|
83.2
|
3.48
|
3.24
|
James
Shields
|
KCR
|
18
|
122.2
|
3.58
|
3.33
|
Derek
Holland*
|
TEX
|
17
|
112.0
|
3.65
|
3.39
|
Based on the above numbers, it would appear that Buchholz, Sale and Scherzer have been the best pitchers in the league this year. Like other metrics, none of these give the ultimate answer though. They do tell us where the pitchers stand if we add hits allowed to FIP though, a perspective which is often ignored.
Well just for fun since this is all I have to add, I ran Max Scherzer's Reverse OE% and he scored .298. Anything under .400 is good, but to be under .300 is really sweet:
ReplyDeleteI also did Sale and Buckholz since they were consistently top 3 in the other stats, so here is the result:
Scherzer .298
Sale .268
Buckholz .263 Wow!