Friday, February 22, 2013

Pitcher's In-Game Peak

With the new season right around the corner, I can't manage to keep my brain from wandering towards baseball. So - after downloading 2012 play-by-play data from Retrosheet - I'm ready to tackle an idea I've toyed with for some time: pitchers' in-game peaks.

In an article I wrote about a year and a half ago I looked into the ability of some pitchers to start a game as strongly as one can: with a no-hitter. Rather than look at elite pitchers who start games exceptionally strong, I wanted to analyze at what point in the game each individual pitcher peaks. The idea of a pitcher being a strong starter or a strong finisher is certainly not a new one and oftentimes an announcer will make mention of a starting pitcher "hitting his stride" at some point in the middle innings. I wanted to develop a way to quantify this effect and to play around with the results.

This is the first of (probably) several posts exploring this effect. For starters, we'll just look at the 2012 season and include all pitchers who started at least 20 games. To find the peak point in each game, I thought 7 consecutive batters sounded about right. This is approximately 2 innings, which when I think of a pitcher hitting his stride seems to fit with how the phrase is typically used. So for every game a pitcher pitched, the stats for every 7-batter period were calculated then added together for the entire season. As an example, the aforementioned Justin Verlander's breakdown looks like this:

BattersStats
1-755.2 IP, 48 H, 18 R, 17 ER, 18 BB, 52 SO, 2.75 ERA,1.186 WHIP,.230/.288/.378
2-858.1 IP, 42 H, 15 R, 14 ER, 17 BB, 59 SO, 2.16 ERA,1.011 WHIP,.200/.258/.286
3-959.0 IP, 42 H, 15 R, 14 ER, 15 BB, 65 SO, 2.14 ERA,0.966 WHIP,.197/.248/.277
4-1059.0 IP, 44 H, 17 R, 16 ER, 13 BB, 67 SO, 2.44 ERA,0.966 WHIP,.204/.248/.301
5-1160.1 IP, 40 H, 14 R, 13 ER, 11 BB, 68 SO, 1.94 ERA,0.845 WHIP,.185/.227/.264
6-1258.2 IP, 45 H, 19 R, 19 ER, 12 BB, 63 SO, 2.91 ERA,0.972 WHIP,.208/.253/.338
7-1359.0 IP, 45 H, 19 R, 19 ER, 11 BB, 64 SO, 2.90 ERA,0.949 WHIP,.207/.249/.341
8-1457.2 IP, 49 H, 22 R, 22 ER, 12 BB, 62 SO, 3.43 ERA,1.058 WHIP,.227/.271/.389
9-1556.1 IP, 53 H, 23 R, 22 ER, 12 BB, 59 SO, 3.51 ERA,1.154 WHIP,.247/.288/.409
10-1655.1 IP, 59 H, 25 R, 24 ER, 10 BB, 55 SO, 3.90 ERA,1.247 WHIP,.271/.304/.440
11-1755.2 IP, 56 H, 21 R, 20 ER, 12 BB, 55 SO, 3.23 ERA,1.222 WHIP,.259/.300/.398
12-1856.1 IP, 58 H, 23 R, 22 ER, 12 BB, 50 SO, 3.51 ERA,1.243 WHIP,.266/.303/.422
13-1957.2 IP, 51 H, 20 R, 19 ER, 13 BB, 51 SO, 2.97 ERA,1.110 WHIP,.236/.281/.338
14-2055.1 IP, 56 H, 21 R, 18 ER, 14 BB, 48 SO, 2.93 ERA,1.265 WHIP,.260/.307/.367
15-2157.0 IP, 50 H, 18 R, 14 ER, 15 BB, 49 SO, 2.21 ERA,1.140 WHIP,.235/.290/.305
16-2257.1 IP, 47 H, 19 R, 15 ER, 17 BB, 47 SO, 2.35 ERA,1.116 WHIP,.222/.286/.297
17-2358.2 IP, 43 H, 21 R, 17 ER, 16 BB, 48 SO, 2.61 ERA,1.006 WHIP,.202/.264/.296
18-2458.2 IP, 43 H, 24 R, 20 ER, 15 BB, 47 SO, 3.07 ERA,0.989 WHIP,.201/.260/.327
19-2557.0 IP, 41 H, 22 R, 17 ER, 15 BB, 49 SO, 2.68 ERA,0.982 WHIP,.194/.254/.308
20-2656.2 IP, 42 H, 17 R, 12 ER, 13 BB, 51 SO, 1.91 ERA,0.971 WHIP,.201/.251/.301
21-2757.0 IP, 35 H, 14 R, 11 ER, 11 BB, 54 SO, 1.74 ERA,0.807 WHIP,.173/.223/.267
22-2853.1 IP, 36 H, 11 R, 9 ER, 10 BB, 55 SO, 1.52 ERA,0.863 WHIP,.185/.228/.277
23-2948.2 IP, 35 H, 12 R, 9 ER, 8 BB, 53 SO, 1.66 ERA,0.884 WHIP,.192/.230/.280

Besides demonstrating in yet another way that Justin Verlander is a pretty good pitcher, his results are very interesting in that his performance to start and end each game is much stronger than his mid-game showing. Is this a trend for him year-to-year? No idea... at least not yet; seems like a good question to investigate down the road. As a quick note on where to stop the anaysis for each pitcher: I found the last batter that a pitcher made it to in at least half of his starts and used this as his endpoint. Verlander's last batter analyzed was #29, indicating that he pitched to at least 29 batters in more than half of his starts but pitched to at least 30 batters in less than half of his starts. This seemed like a good cut-off. 

Now that we have the 7-batter summaries for each pitcher, we can find their best 7-batter range. "Best," of course, is highly subjective and depends on what statistic(s) we use. I toyed with using Runs Created but settled on FIP (Fielding Independent Pitching) as the single number to use. The best 7-batter range, then, is the one with the best FIP. FIP is an estimate of what a pitcher's ERA should have been based on only those things that a pitcher has been proven to have control over: home runs, strikeouts and walks. While imperfect, I settled on it over raw ERA since we're dealing with such small sample sets and also because at the end of outings, ERA becomes skewed by a good or bad bullpen and I wanted a number to isolate the starting pitcher's performance only.

Without further delay, I'll present the results. I intend to refine this method a bit and explore historical results (with many thanks to Retrosheet's tireless work, we're looking at a good chunk of play-by-play data all the way back to 1945 now... huzzah!) in the future but this will serve as a good introduction. In the results tables below, you will find:
- The pitcher's name
- Their peak batter range
- How many runs better (using FIP) this pitcher was during their peak than the season as a whole:
- How many total starts that pitcher made
- The last better analyzed for that pitcher. ie: The last batter the pitcher made it to in at least half of his starts.

Early Starters (Best stretch = Batters 1 to 7)
Pitcher
Peak Batters
Runs Better
Starts
Last Batter
Tommy Hunter
1-7
1.50
20
26
Jon Lester
1-7
1.28
33
27
R.A. Dickey
1-7
1.24
33
28
Matt Moore
1-7
1.08
31
25
Marco Estrada
1-7
1.08
23
24

Strong Closers (Best stretch = Last 7 batters faced)
PitcherPeak BattersRuns BetterStartsLast Batter
Kyle Kendrick20-261.342526
Jose Quintana20-260.772226


In addition to their peak period, I also determined their valley period: the 7-batter range in which each pitcher struggled the most.

Slow Starters (Worst stretch = Batters 1 to 7)
PitcherWorst BattersRuns WorseStartsLast Batter
Kyle Kendrick1-7-2.312526
Jeff Francis1-7-1.962421
Yovani Gallardo1-7-1.363327
Jose Quintana1-7-1.242226
Barry Zito1-7-1.223226
James McDonald1-7-1.152924
Cliff Lee1-7-1.063029
Homer Bailey1-7-1.013328
Gavin Floyd1-7-1.002926
Brandon Morrow1-7-1.002126
Josh Johnson1-7-0.903126
Doug Fister1-7-0.832626
Jaime Garcia1-7-0.792027
Kevin Correia1-7-0.752823
Alex Cobb1-7-0.582326


An intriguing (to me) idea I have here is to use this data as a way of judging a manager's skill in pulling a pitcher at the right time. That Zach McAllister was over three and half runs per game worse during the last seven batters he faced probably indicates that Terry Francona's hook should be a little quicker than Manny Acta's was.

Bad Finishers (Worst stretch = Last 7 Batters Faced)
PitcherWorst BattersRuns WorseStartsLast Batter
Zach McAllister19-25-3.622225
Chris Young19-25-2.722025
Luis Mendoza21-27-2.242527
Trevor Cahill20-26-1.683226
Felix Doubront19-25-1.582925
Marco Estrada18-24-1.482324
Derek Lowe21-27-1.452127
Joe Blanton21-27-1.433027
R.A. Dickey22-28-1.343328
Jordan Lyles19-25-1.342525
Rick Porcello20-26-1.193126
Wei-Yin Chen20-26-1.043226
Bruce Chen19-25-0.963425
Jason Marquis20-26-0.962226
Scott Diamond21-27-0.862727
Gio Gonzalez19-25-0.823225
Michael Fiers19-25-0.732225
Kevin Millwood19-25-0.582825
Jeremy Hellickson18-24-0.573124
Blake Beavan19-25-0.392625

All pitchers, 2012:
Pitcher
Peak Batters
Runs Better
Worst Batters
Runs Worse
Starts
Last Batter
Henderson Alvarez
5-11
1.15
19-25
-0.80
31
26
Bronson Arroyo
3-9
0.65
10-16
-1.28
32
27
Homer Bailey
6-12
1.08
1-7
-1.01
33
28
Blake Beavan
14-20
1.93
19-25
-0.39
26
25
Josh Beckett
2-8
1.12
10-16
-1.34
28
27
Erik Bedard
3-9
0.90
10-16
-1.77
24
24
Chad Billingsley
9-15
1.05
2-8
-0.74
25
26
Joe Blanton
14-20
1.29
21-27
-1.43
30
27
Clay Buchholz
22-28
0.98
2-8
-1.56
29
29
Mark Buehrle
14-20
0.51
19-25
-1.10
31
27
Madison Bumgarner
5-11
0.92
20-26
-1.25
32
27
A.J. Burnett
13-19
0.93
20-26
-1.47
31
28
Trevor Cahill
5-11
1.71
20-26
-1.68
32
26
Matt Cain
17-23
0.81
21-27
-1.10
32
28
Chris Capuano
6-12
0.78
19-25
-1.32
33
26
Wei-Yin Chen
5-11
0.96
20-26
-1.04
32
26
Bruce Chen
14-20
1.38
19-25
-0.96
34
25
Alex Cobb
14-20
0.77
1-7
-0.58
23
26
Bartolo Colon
15-21
0.70
9-15
-1.11
24
28
Kevin Correia
7-13
1.57
1-7
-0.75
28
23
Johnny Cueto
20-26
0.44
13-19
-0.78
33
27
Yu Darvish
3-9
0.94
10-16
-1.05
29
28
Ryan Dempster
3-9
1.43
10-16
-1.63
28
27
Ross Detwiler
16-22
0.71
10-16
-0.55
27
24
Scott Diamond
6-12
0.94
21-27
-0.86
27
27
R.A. Dickey
1-7
1.24
22-28
-1.34
33
28
Felix Doubront
5-11
0.99
19-25
-1.58
29
25
Nathan Eovaldi
15-21
1.44
10-16
-0.98
22
25
Marco Estrada
1-7
1.08
18-24
-1.48
23
24
Scott Feldman
12-18
0.98
4-10
-2.10
21
25
Michael Fiers
4-10
0.69
19-25
-0.73
22
25
Doug Fister
17-23
0.59
1-7
-0.83
26
26
Gavin Floyd
14-20
0.84
1-7
-1.00
29
26
Jeff Francis
14-20
1.77
1-7
-1.96
24
21
Yovani Gallardo
16-22
2.08
1-7
-1.36
33
27
Jaime Garcia
17-23
0.70
1-7
-0.79
20
27
Gio Gonzalez
15-21
0.85
19-25
-0.82
32
25
Zack Greinke
15-21
0.82
20-26
-0.67
34
27
Jeremy Guthrie
18-24
1.93
11-17
-2.98
29
26
Roy Halladay
6-12
0.85
20-26
-1.97
25
27
Cole Hamels
5-11
0.55
16-22
-1.01
31
28
Jason Hammel
15-21
0.69
8-14
-0.47
20
24
Tommy Hanson
5-11
1.27
10-16
-1.51
31
24
J.A. Happ
14-20
1.15
2-8
-1.15
24
24
Aaron Harang
5-11
0.91
11-17
-1.08
31
26
Dan Haren
10-16
0.75
3-9
-0.91
30
25
Lucas Harrell
4-10
0.91
10-16
-1.36
32
26
Matt Harrison
3-9
0.67
21-27
-0.99
32
28
Jeremy Hellickson
5-11
0.42
18-24
-0.57
31
24
Felix Hernandez
5-11
0.72
15-21
-0.52
33
29
Luke Hochevar
14-20
0.89
7-13
-1.55
32
26
Derek Holland
2-8
1.46
20-26
-2.14
27
28
Tim Hudson
3-9
0.88
20-26
-1.62
28
27
Phil Hughes
4-10
1.39
9-15
-1.59
32
27
Tommy Hunter
1-7
1.50
13-19
-3.35
20
26
Edwin Jackson
4-10
1.03
11-17
-1.11
31
27
Ubaldo Jimenez
4-10
1.17
11-17
-0.86
31
26
Josh Johnson
18-24
0.84
1-7
-0.90
31
26
Kyle Kendrick
20-26
1.34
1-7
-2.31
25
26
Ian Kennedy
3-9
1.03
10-16
-1.59
33
28
Clayton Kershaw
4-10
0.98
11-17
-1.38
33
28
Hiroki Kuroda
14-20
0.87
20-26
-1.15
33
27
Mat Latos
5-11
1.52
19-25
-1.03
33
26
Mike Leake
4-10
1.26
11-17
-1.52
30
27
Cliff Lee
14-20
1.01
1-7
-1.06
30
29
Jon Lester
1-7
1.28
11-17
-2.38
33
27
Tim Lincecum
15-21
0.68
2-8
-0.84
33
26
Francisco Liriano
7-13
1.13
3-9
-0.94
28
23
Kyle Lohse
15-21
1.03
11-17
-0.59
33
26
Derek Lowe
5-11
1.40
21-27
-1.45
21
27
Jordan Lyles
15-21
1.23
19-25
-1.34
25
25
Lance Lynn
4-10
1.34
10-16
-1.17
29
25
Paul Maholm
3-9
0.79
11-17
-1.58
31
26
Shaun Marcum
15-21
0.90
2-8
-1.16
21
26
Jason Marquis
5-11
1.87
20-26
-0.96
22
26
Justin Masterson
2-8
1.47
12-18
-1.56
34
27
Zach McAllister
11-17
1.89
19-25
-3.62
22
25
James McDonald
5-11
1.26
1-7
-1.15
29
24
Luis Mendoza
6-12
0.85
21-27
-2.24
25
27
Wade Miley
5-11
1.33
16-22
-1.61
29
27
Kevin Millwood
5-11
0.65
19-25
-0.58
28
25
Tom Milone
14-20
0.31
11-17
-1.28
31
26
Mike Minor
5-11
1.26
13-19
-1.22
30
24
Matt Moore
1-7
1.08
10-16
-1.46
31
25
Brandon Morrow
11-17
1.43
1-7
-1.00
21
26
Jonathon Niese
15-21
1.02
2-8
-0.94
30
27
Ricky Nolasco
5-11
0.75
10-16
-0.55
31
27
Bud Norris
6-12
0.79
13-19
-1.39
29
26
Ivan Nova
5-11
0.87
17-23
-0.98
28
27
Jarrod Parker
11-17
0.57
5-11
-0.87
29
27
Jake Peavy
14-20
1.02
21-27
-1.64
32
28
Drew Pomeranz
5-11
2.20
11-17
-3.30
22
19
Rick Porcello
5-11
1.07
20-26
-1.19
31
26
David Price
7-13
0.42
16-22
-0.95
31
27
Jose Quintana
20-26
0.77
1-7
-1.24
22
26
Clayton Richard
8-14
1.88
19-25
-2.05
33
28
Wandy Rodriguez
18-24
1.20
2-8
-2.32
33
27
Ricky Romero
9-15
1.26
3-9
-1.06
32
27
C.C. Sabathia
2-8
0.67
9-15
-1.17
28
30
Chris Sale
7-13
0.89
19-25
-1.85
29
27
Jeff Samardzija
17-23
1.09
10-16
-1.35
28
26
Anibal Sanchez
5-11
1.06
18-24
-0.98
31
27
Ervin Santana
14-20
1.70
8-14
-1.43
30
27
Johan Santana
7-13
2.02
10-16
-0.76
21
24
Joe Saunders
3-9
1.59
11-17
-3.09
28
27
Max Scherzer
12-18
0.29
16-22
-1.07
32
26
James Shields
22-28
0.67
16-22
-1.12
33
29
Stephen Strasburg
3-9
0.56
10-16
-1.12
28
24
Jason Vargas
5-11
1.57
16-22
-1.42
33
27
Justin Verlander
3-9
1.26
10-16
-0.90
33
29
Ryan Vogelsong
17-23
0.58
10-16
-0.84
31
26
Edinson Volquez
15-21
0.58
11-17
-0.69
32
26
Chris Volstad
16-22
1.49
10-16
-1.19
21
25
Adam Wainwright
6-12
1.06
11-17
-0.75
32
26
Jered Weaver
7-13
0.97
11-17
-0.89
30
27
Jake Westbrook
6-12
1.26
17-23
-1.02
28
27
Alex White
14-20
0.52
11-17
-0.75
20
21
C.J. Wilson
7-13
0.66
12-18
-1.05
34
27
Randy Wolf
7-13
1.00
19-25
-1.18
26
26
Travis Wood
3-9
0.85
10-16
-1.33
26
25
Vance Worley
4-10
2.27
14-20
-1.78
23
27
Chris Young
5-11
2.11
19-25
-2.72
20
25
Carlos Zambrano
16-22
0.51
19-25
-1.29
20
26
Jordan Zimmermann
4-10
0.62
16-22
-0.86
32
26
Barry Zito
17-23
1.00
1-7
-1.22
32
26