May 24, 2013
What Makes a Good Changeup?
An Investigation, Part Two
by Harry Pavlidis
Two weeks ago, I looked at some of the factors that may impact "changeup" quality. When dealing with major-league pitchers, you are dealing with a rather select sample, so all results should be handled with care. In other words, this isn't a roapmap to pitcher development, but a single marker on the road.
Let's recap some of part one:
- The faster a pitcher's fastball, the more likely he was to get whiffs with his changeup.
- The difference in a pitcher's fastball and changeup velocity had a similar relationship.
- Pitchers with high changeup whiff rates threw the changeup more often.
- The vertical "drop" of the changeups relative to fastballs impacted the whiff rates that the pitch induced.
I thought that ground-ball rates would be less interesting than whiff rates, and left them out of part one, but the evidence suggests that I was wrong.
- The mild relationship between fastball speed and changeup whiffs is retained with ground balls
- There is a strong relationship between changeup velocity and ground balls—higher-velocity changeups induce more grounders.
- Changeup speed doesn't impact whiff rate, so this seems like a winning move (but see the caveat in point 5).
- The smaller the gap between fastball and changeup speed, the more grounders a pitcher induces on changeups.
- Increasing changeup speed but not fastball speed will hurt whiff rates, a gigantic caveat to point 3.
- The more sink, the better—no surprise here. Also, the more the changeup sinks relative to the fastball, the greater the ground-ball rates it induces.
Let's put those together:
- Hey, velocity is good!
- If you throw a hard changeup (relative to the fastball), you're trading more ground balls for fewer whiffs
- Power pitchers (big fastball and a good gap to the changeup) get the best of both worlds (whiffs and grounders)
- The bigger the drop, the better—sink it, and sink it more than the fastball, and you'll miss bats and get grounders.
So, we've learned that a hard sinking changeup is a good thing. Shocker. We've also learned that the amount of tail on the pitch—on its own or relative to the fastball—isn't an apparent factor. Based on this analysis so far, it would seem that being both a bat-misser and a worm-killer is a neat trick. We'd expect the pitchers with both abilities to fit the model outlined above: big fastball, good gap to the changeup in speed and drop. On the other end of the spectrum, we'd find pitchers who neither miss bats nor kill worms with their changeups. Here's where we'd expect a small pair of gaps and a general lack of velocity.
This complicated-looking chart shows ground-ball rate on the y-axis and whiff rate on the x-axis. The cross hair in the middle is the intersection of the two distributions' means. The rings are approximately one standard deviation (both rates have comparable if not nearly identical standard deviations around .088). The green line is the linear relationship between the two rates, which, as you can see, is mildly positive but not particularly powerful.
The tables below summarize the pitchers in two quadrants and include the "ring" of the chart into which they fall. The mean ground-ball rate is .505, and .295 cuts the pack in half for whiff rate. A summary of all four groups is shown before the top-right and bottom-left quadrant details. Reminder: the data covers 2011, 2012, and part of 2013.
Table Key
|
MPH
|
changeup speed
|
|
pfx
|
horizontal movement
|
|
pfz
|
vertical drop
|
|
Swing
|
swings per pitch
|
|
Whiff
|
whiffs per swing
|
|
Chase
|
swings per out of zone
|
|
GB
|
ground balls per ball in play
|
|
fMPH
|
fastball speed
|
|
gapMPH
|
fastball speed minus changeup speed
|
|
gappfz
|
changeup drop minus fastball drop
|
|
ring
|
summed z-scores of Whiff and GB rates
|
Averages
|
Group
|
MPH
|
Whiff
|
GB
|
fMPH
|
gapMPH
|
gappfz
|
|
Top-right
|
85.3
|
.38
|
.59
|
92.8
|
7.5
|
12.4
|
|
Bottom-left
|
83.1
|
.22
|
.44
|
91.2
|
8.1
|
9.6
|
|
Top-left
|
84.3
|
.24
|
.57
|
91.1
|
6.9
|
10.5
|
|
Bottom-right
|
82.0
|
.36
|
.44
|
91.4
|
9.4
|
11.7
|
Some extra details are included with the pitchers so you can reference the background on swing and chase rates in the first part of this series.
Top-right (the good)
|
First
|
Last
|
MPH
|
pfx
|
pfz
|
Swing
|
Whiff
|
Chase
|
GB
|
fMPH
|
gapMPH
|
gappfz
|
ring
|
|
Stephen
|
Strasburg
|
89
|
12
|
25
|
0.52
|
0.54
|
0.45
|
0.65
|
96
|
7.1
|
12.9
|
5
|
|
Hisashi
|
Iwakuma
|
87
|
9
|
33
|
0.64
|
0.35
|
0.55
|
0.78
|
91
|
4.1
|
13.2
|
4
|
|
Cole
|
Hamels
|
84
|
11
|
25
|
0.61
|
0.50
|
0.51
|
0.61
|
92
|
8.1
|
13.3
|
4
|
|
A.J.
|
Burnett
|
89
|
8
|
27
|
0.44
|
0.31
|
0.31
|
0.77
|
93
|
4.6
|
10.2
|
3
|
|
Jeff
|
Samardzija
|
86
|
7
|
25
|
0.55
|
0.46
|
0.42
|
0.59
|
96
|
9.5
|
11.4
|
3
|
|
Hisanori
|
Takahashi
|
81
|
14
|
29
|
0.58
|
0.43
|
0.52
|
0.62
|
90
|
8.7
|
13.4
|
3
|
|
Jonathan
|
Papelbon
|
89
|
11
|
27
|
0.60
|
0.35
|
0.54
|
0.70
|
95
|
5.7
|
13.4
|
3
|
|
J.J.
|
Putz
|
86
|
6
|
28
|
0.62
|
0.47
|
0.54
|
0.58
|
93
|
7.2
|
15.1
|
3
|
|
Ricky
|
Romero
|
85
|
9
|
34
|
0.50
|
0.41
|
0.39
|
0.62
|
92
|
7.5
|
14.5
|
3
|
|
Gio
|
Gonzalez
|
85
|
12
|
27
|
0.43
|
0.39
|
0.30
|
0.63
|
94
|
8.6
|
11.3
|
3
|
|
Hiroki
|
Kuroda
|
87
|
6
|
28
|
0.49
|
0.40
|
0.41
|
0.61
|
92
|
5.5
|
10.4
|
2
|
|
Fernando
|
Rodney
|
83
|
12
|
28
|
0.46
|
0.48
|
0.41
|
0.53
|
97
|
13.2
|
14.5
|
2
|
|
Roy
|
Halladay
|
83
|
9
|
33
|
0.59
|
0.39
|
0.52
|
0.61
|
92
|
8.5
|
12.6
|
2
|
|
Felix
|
Hernandez
|
90
|
7
|
30
|
0.61
|
0.35
|
0.52
|
0.64
|
93
|
3.6
|
11.0
|
2
|
|
Randall
|
Delgado
|
83
|
11
|
28
|
0.53
|
0.41
|
0.43
|
0.57
|
93
|
10.1
|
13.0
|
2
|
|
Kelvin
|
Herrera
|
88
|
13
|
26
|
0.61
|
0.38
|
0.52
|
0.60
|
99
|
11.6
|
15.3
|
2
|
|
Francisco
|
Liriano
|
86
|
14
|
25
|
0.44
|
0.43
|
0.32
|
0.53
|
93
|
7.5
|
7.8
|
2
|
|
Edinson
|
Volquez
|
84
|
9
|
31
|
0.50
|
0.41
|
0.39
|
0.55
|
94
|
10.1
|
14.9
|
2
|
|
Jim
|
Johnson
|
89
|
11
|
23
|
0.64
|
0.32
|
0.54
|
0.64
|
95
|
6.7
|
7.2
|
2
|
|
Tim
|
Lincecum
|
84
|
3
|
28
|
0.51
|
0.41
|
0.41
|
0.55
|
92
|
7.7
|
15.0
|
2
|
|
Zack
|
Greinke
|
86
|
11
|
27
|
0.47
|
0.32
|
0.37
|
0.64
|
93
|
7.3
|
13.4
|
2
|
|
James
|
Shields
|
85
|
10
|
26
|
0.58
|
0.37
|
0.48
|
0.58
|
92
|
7.1
|
12.7
|
2
|
|
Edward
|
Mujica
|
87
|
10
|
29
|
0.61
|
0.30
|
0.51
|
0.65
|
93
|
5.6
|
13.4
|
2
|
|
Miguel
|
Gonzalez
|
83
|
6
|
30
|
0.60
|
0.41
|
0.51
|
0.54
|
92
|
8.8
|
18.0
|
2
|
|
Felix
|
Doubront
|
86
|
13
|
29
|
0.50
|
0.39
|
0.39
|
0.55
|
93
|
7.3
|
14.7
|
2
|
|
Jon
|
Lester
|
86
|
14
|
26
|
0.52
|
0.33
|
0.38
|
0.61
|
93
|
7.4
|
11.0
|
2
|
|
Randy
|
Wells
|
82
|
10
|
28
|
0.50
|
0.40
|
0.40
|
0.53
|
89
|
6.8
|
9.7
|
1
|
|
Homer
|
Bailey
|
87
|
8
|
26
|
0.48
|
0.32
|
0.36
|
0.61
|
93
|
6.6
|
11.6
|
1
|
|
C.C.
|
Sabathia
|
87
|
11
|
22
|
0.56
|
0.34
|
0.40
|
0.59
|
93
|
6.7
|
7.3
|
1
|
|
Matt
|
Reynolds
|
83
|
8
|
31
|
0.61
|
0.37
|
0.47
|
0.55
|
90
|
6.9
|
15.7
|
1
|
|
Cristhian
|
Martinez
|
83
|
13
|
32
|
0.65
|
0.35
|
0.54
|
0.57
|
90
|
7.4
|
10.5
|
1
|
|
Johnny
|
Cueto
|
84
|
7
|
30
|
0.55
|
0.31
|
0.45
|
0.61
|
94
|
9.4
|
14.7
|
1
|
|
Joe
|
Blanton
|
84
|
9
|
24
|
0.56
|
0.36
|
0.45
|
0.54
|
91
|
7.0
|
10.4
|
1
|
|
Dillon
|
Gee
|
83
|
12
|
30
|
0.53
|
0.36
|
0.45
|
0.54
|
90
|
7.0
|
12.3
|
1
|
|
Justin
|
Verlander
|
86
|
12
|
22
|
0.55
|
0.36
|
0.44
|
0.52
|
95
|
8.8
|
10.9
|
1
|
|
Jason
|
Frasor
|
87
|
8
|
30
|
0.48
|
0.35
|
0.39
|
0.53
|
94
|
6.8
|
17.1
|
1
|
|
Josh
|
Beckett
|
88
|
10
|
25
|
0.49
|
0.32
|
0.36
|
0.56
|
93
|
4.8
|
9.5
|
1
|
|
Kyle
|
Kendrick
|
83
|
12
|
28
|
0.58
|
0.34
|
0.48
|
0.53
|
91
|
7.5
|
9.1
|
1
|
|
Jake
|
Peavy
|
84
|
9
|
29
|
0.51
|
0.30
|
0.39
|
0.57
|
92
|
7.8
|
13.6
|
1
|
|
Trevor
|
Cahill
|
81
|
9
|
35
|
0.51
|
0.32
|
0.40
|
0.54
|
90
|
8.6
|
10.6
|
1
|
Note: The top five of Strasburg, Iwakuma, and Hamels can be considered a group of elite off-speed pitchers. I don't think anyone would quibble with that.
Bottom-left (the bad)
|
First
|
Last
|
MPH
|
pfx
|
pfz
|
Swing
|
Whiff
|
Chase
|
GB
|
fMPH
|
gapMPH
|
gappfz
|
ring
|
|
Vance
|
Worley
|
84
|
7
|
22
|
0.42
|
0.10
|
0.26
|
0.35
|
91
|
6.5
|
5.7
|
4
|
|
Randy
|
Wolf
|
79
|
13
|
29
|
0.44
|
0.14
|
0.27
|
0.35
|
89
|
10.0
|
11.3
|
4
|
|
Derek
|
Holland
|
85
|
13
|
20
|
0.46
|
0.15
|
0.23
|
0.40
|
94
|
9.1
|
5.1
|
3
|
|
Guillermo
|
Moscoso
|
81
|
10
|
25
|
0.44
|
0.27
|
0.30
|
0.28
|
92
|
11.0
|
12.6
|
3
|
|
Bruce
|
Chen
|
78
|
11
|
29
|
0.50
|
0.24
|
0.32
|
0.32
|
87
|
9.0
|
10.5
|
3
|
|
Jo-Jo
|
Reyes
|
84
|
10
|
25
|
0.56
|
0.22
|
0.34
|
0.34
|
91
|
6.8
|
8.3
|
3
|
|
Josh
|
Tomlin
|
82
|
9
|
28
|
0.51
|
0.15
|
0.29
|
0.43
|
89
|
7.2
|
12.8
|
3
|
|
Jair
|
Jurrjens
|
84
|
9
|
23
|
0.51
|
0.13
|
0.36
|
0.47
|
90
|
6.0
|
7.5
|
2
|
|
Matt
|
Garza
|
86
|
9
|
20
|
0.46
|
0.22
|
0.30
|
0.38
|
94
|
8.1
|
7.5
|
2
|
|
Bronson
|
Arroyo
|
79
|
6
|
31
|
0.45
|
0.17
|
0.29
|
0.44
|
88
|
8.7
|
10.6
|
2
|
|
C.J.
|
Wilson
|
85
|
11
|
23
|
0.41
|
0.20
|
0.21
|
0.41
|
92
|
6.6
|
4.9
|
2
|
|
Aaron
|
Harang
|
83
|
8
|
24
|
0.44
|
0.14
|
0.27
|
0.48
|
90
|
7.3
|
9.3
|
2
|
|
J.A.
|
Happ
|
83
|
10
|
21
|
0.46
|
0.19
|
0.26
|
0.43
|
91
|
8.4
|
8.4
|
2
|
|
Mike
|
Leake
|
84
|
10
|
25
|
0.47
|
0.19
|
0.29
|
0.43
|
90
|
5.9
|
4.2
|
2
|
|
Nick
|
Blackburn
|
83
|
8
|
25
|
0.53
|
0.23
|
0.34
|
0.40
|
91
|
7.3
|
5.5
|
2
|
|
Jonathon
|
Niese
|
85
|
11
|
25
|
0.35
|
0.17
|
0.19
|
0.46
|
91
|
6.4
|
8.4
|
2
|
|
Bud
|
Norris
|
85
|
8
|
25
|
0.47
|
0.18
|
0.31
|
0.46
|
93
|
8.3
|
12.4
|
2
|
|
Mat
|
Latos
|
84
|
2
|
24
|
0.43
|
0.27
|
0.26
|
0.37
|
93
|
9.4
|
11.6
|
2
|
|
Chad
|
Billingsley
|
86
|
10
|
25
|
0.41
|
0.16
|
0.25
|
0.48
|
92
|
6.3
|
9.4
|
2
|
|
Colby
|
Lewis
|
83
|
9
|
23
|
0.46
|
0.25
|
0.33
|
0.39
|
89
|
6.1
|
9.0
|
2
|
|
Phil
|
Hughes
|
85
|
10
|
22
|
0.47
|
0.17
|
0.32
|
0.47
|
93
|
7.9
|
9.8
|
2
|
|
Roy
|
Oswalt
|
83
|
10
|
28
|
0.57
|
0.16
|
0.41
|
0.49
|
92
|
9.4
|
13.7
|
2
|
|
Joe
|
Saunders
|
81
|
13
|
27
|
0.43
|
0.20
|
0.30
|
0.45
|
90
|
8.5
|
8.5
|
2
|
|
Danny
|
Duffy
|
85
|
12
|
22
|
0.40
|
0.22
|
0.19
|
0.43
|
95
|
9.9
|
11.5
|
2
|
|
Luke
|
Hochevar
|
84
|
10
|
25
|
0.40
|
0.16
|
0.25
|
0.49
|
93
|
9.7
|
10.2
|
2
|
|
Barry
|
Zito
|
75
|
10
|
35
|
0.49
|
0.23
|
0.32
|
0.42
|
84
|
9.1
|
17.0
|
2
|
|
Travis
|
Wood
|
79
|
13
|
30
|
0.50
|
0.29
|
0.35
|
0.37
|
90
|
10.8
|
16.3
|
2
|
|
Brian
|
Matusz
|
83
|
6
|
19
|
0.49
|
0.22
|
0.27
|
0.44
|
91
|
7.5
|
7.0
|
2
|
|
David
|
Price
|
84
|
14
|
24
|
0.49
|
0.25
|
0.31
|
0.43
|
96
|
11.3
|
9.4
|
1
|
|
Erik
|
Bedard
|
78
|
10
|
32
|
0.45
|
0.27
|
0.30
|
0.41
|
91
|
12.5
|
15.7
|
1
|
|
Josh
|
Outman
|
81
|
10
|
28
|
0.44
|
0.28
|
0.23
|
0.40
|
93
|
12.7
|
14.1
|
1
|
|
Jordan
|
Lyles
|
82
|
9
|
27
|
0.49
|
0.28
|
0.31
|
0.40
|
92
|
9.7
|
10.1
|
1
|
|
Anthony
|
Bass
|
84
|
6
|
25
|
0.45
|
0.23
|
0.28
|
0.46
|
93
|
9.0
|
10.1
|
1
|
|
Ross
|
Detwiler
|
85
|
11
|
24
|
0.47
|
0.20
|
0.24
|
0.49
|
93
|
8.1
|
7.5
|
1
|
|
Rick
|
Porcello
|
83
|
11
|
28
|
0.50
|
0.27
|
0.41
|
0.42
|
92
|
8.9
|
7.9
|
1
|
|
Mike
|
Minor
|
85
|
14
|
23
|
0.56
|
0.28
|
0.38
|
0.41
|
91
|
6.6
|
8.1
|
1
|
|
Philip
|
Humber
|
85
|
9
|
25
|
0.47
|
0.19
|
0.24
|
0.50
|
91
|
6.3
|
9.3
|
1
|
|
Frank
|
Francisco
|
86
|
7
|
25
|
0.45
|
0.29
|
0.30
|
0.41
|
95
|
8.9
|
14.9
|
1
|
|
Jason
|
Marquis
|
81
|
9
|
30
|
0.44
|
0.21
|
0.32
|
0.50
|
89
|
8.1
|
7.1
|
1
|
|
Carlos
|
Villanueva
|
82
|
6
|
26
|
0.53
|
0.24
|
0.34
|
0.47
|
89
|
7.8
|
12.1
|
1
|
|
Jeremy
|
Guthrie
|
85
|
8
|
24
|
0.47
|
0.23
|
0.31
|
0.49
|
93
|
8.4
|
9.3
|
1
|
|
Jason
|
Hammel
|
88
|
10
|
24
|
0.53
|
0.24
|
0.36
|
0.49
|
94
|
6.2
|
9.0
|
1
|
|
Jhoulys
|
Chacin
|
85
|
4
|
25
|
0.47
|
0.23
|
0.30
|
0.50
|
91
|
6.6
|
6.6
|
1
|
|
Chris
|
Tillman
|
82
|
6
|
21
|
0.56
|
0.27
|
0.37
|
0.46
|
92
|
10.0
|
10.1
|
1
|
|
Ryan
|
Vogelsong
|
84
|
11
|
25
|
0.49
|
0.25
|
0.32
|
0.48
|
92
|
7.7
|
9.3
|
1
|
|
Scott
|
Diamond
|
84
|
10
|
21
|
0.48
|
0.23
|
0.30
|
0.50
|
90
|
5.6
|
5.5
|
1
|
|
Douglas
|
Fister
|
83
|
12
|
29
|
0.56
|
0.24
|
0.45
|
0.50
|
90
|
7.5
|
8.9
|
1
|
|
Brian
|
Duensing
|
85
|
14
|
25
|
0.47
|
0.24
|
0.30
|
0.50
|
92
|
7.5
|
7.9
|
1
|
|
Cliff
|
Lee
|
85
|
12
|
22
|
0.56
|
0.28
|
0.39
|
0.46
|
92
|
6.8
|
8.3
|
1
|
|
Tom
|
Gorzelanny
|
84
|
13
|
26
|
0.51
|
0.24
|
0.34
|
0.50
|
91
|
6.5
|
8.7
|
1
|
|
Mark
|
Buehrle
|
79
|
10
|
30
|
0.56
|
0.25
|
0.41
|
0.50
|
86
|
6.6
|
9.5
|
1
|
|
Jeff
|
Karstens
|
81
|
8
|
30
|
0.50
|
0.26
|
0.35
|
0.49
|
90
|
8.5
|
11.4
|
1
|
|
Edwin
|
Jackson
|
87
|
11
|
20
|
0.44
|
0.27
|
0.28
|
0.48
|
95
|
7.4
|
7.1
|
1
|
|
Lucas
|
Harrell
|
83
|
8
|
26
|
0.47
|
0.26
|
0.33
|
0.49
|
93
|
9.6
|
8.4
|
1
|
|
Jeff
|
Francis
|
77
|
8
|
35
|
0.55
|
0.25
|
0.42
|
0.50
|
86
|
8.3
|
13.2
|
1
|
|
Alfredo
|
Aceves
|
86
|
10
|
23
|
0.52
|
0.26
|
0.35
|
0.49
|
94
|
7.9
|
8.2
|
1
|
|
Wei-Yin
|
Chen
|
85
|
12
|
21
|
0.48
|
0.26
|
0.30
|
0.50
|
92
|
7.1
|
8.6
|
1
|
|
Kyle
|
Lohse
|
81
|
10
|
30
|
0.63
|
0.29
|
0.49
|
0.47
|
90
|
9.5
|
13.7
|
0
|
|
Jake
|
Arrieta
|
88
|
9
|
22
|
0.41
|
0.28
|
0.28
|
0.49
|
94
|
6.2
|
9.1
|
0
|
Note: "Bad" is a relative term, especially when referring to the guys in the lower "rings”; they're not far from average, and all of these guys are major leaguers. What's not even considered is how a changeup may set up something else (pitching backward) or whether some pitchers’ shaky changeups are even relevant.
This series was initially going to consist of three parts. To cover all the interesting details here, I might need five.
Harry Pavlidis is an author of Baseball Prospectus.
Click here to see Harry's other articles.
You can contact Harry by clicking here
Transaction Analysis: ... (05/24)
17 comments have been left for this article. 
Fantasy Freestyle: The Myths of Minor-League...
Apologies if I'm missing this. Reading in https format at work, can't see the graph, might be limited in other ways. But is home-run vulnerability addressed? Intuitively, I might think firmer changeups or ones with smaller gaps would result in fewer total flies, but harder-hit flies. Maybe that's silly. Just a question. I love this piece.
it's a good question, I haven't looked into that...yet.