A couple weeks back, I attempted to answer the question, Whose Better - Gerrit Cole or Michael Wacha? I did so through the use of pitch repertoire skills on the "sabermetric outcome" level.
Since, I've upgraded the approach. Through the use of z-scores, let's say I came up with 3 scores initially:
1) I combined Velocity and both Horizontal & Verticle Movement
2) I combined GB/FB and LD/BIP
3) I then combined the Balls In Play (BIP) related z-score and the Whiff/Swing z-score together
There was certainly some value, but I'm revising this approach here. Velocity and Movement is a feature of the pitch prior to the outcome. I want to stay on the outcome level. This time around I am combining the following 3 z-scores:
1) Whiff/Swing
2) GB/FB
3) LD/BIP
This time, I'm also weighing each z-score by their correlation to an average of ERA, xFIP and SIERA (actual and expected ERA's) for data since 2010, which outputted the following correlations respectively: -.6464, -.06694 and .0593...significant and then relatively insignificant correlations to ERA and expected ERA's, but all in the right direction.
Why Whiff/Swing, GB/FB and LD/BIP? Because that's what is available in Baseball Prospectus' Pitch F/X Leaderboard. IMO, it's missing HR/(FB+LD) and IFFB or PU/BIP, which you can find in Brooks Baseball's Pitcher Cards' Sabermetric Outcome Level.
This presentation therefore certainly has limitations - HR/FB at least has a .377 correlation and IFFB% on its own has a -.14 correlation to the same ERA-related average. You will hopefully see it still has value.
Here I will include just the "25 best sliders" from last year for a pitch count over 100:
|
RK |
Player |
Tm |
H |
Count |
Whf/Sw |
zWhf/Sw |
Fouls/Sw |
GB/FB |
zGB/FB |
GB/BIP |
LD/BIP |
zLD/BIP |
FB/BIP |
Pitch Score |
|
1 |
ARI |
L |
703 |
0.52 |
2.64 |
0.25 |
1.77 |
-0.26 |
0.47 |
0.19 |
-0.36 |
0.27 |
1.67 |
|
|
2 |
SDN |
R |
504 |
0.50 |
2.38 |
0.19 |
3.47 |
1.38 |
0.70 |
0.06 |
-2.34 |
0.20 |
1.49 |
|
|
3 |
TEX |
L |
777 |
0.48 |
2.06 |
0.30 |
0.96 |
-1.04 |
0.28 |
0.32 |
1.63 |
0.29 |
1.36 |
|
|
4 |
NYN |
R |
106 |
0.46 |
1.84 |
0.19 |
2.20 |
0.16 |
0.50 |
0.23 |
0.26 |
0.23 |
1.21 |
|
|
5 |
TEX |
R |
575 |
0.46 |
1.81 |
0.25 |
1.64 |
-0.38 |
0.43 |
0.22 |
0.10 |
0.27 |
1.15 |
|
|
6 |
CIN |
R |
790 |
0.42 |
1.32 |
0.27 |
5.57 |
3.41 |
0.58 |
0.28 |
1.02 |
0.10 |
1.14 |
|
|
7 |
DET |
R |
517 |
0.46 |
1.77 |
0.23 |
1.76 |
-0.27 |
0.44 |
0.12 |
-1.43 |
0.25 |
1.04 |
|
|
8 |
PIT |
L |
900 |
0.41 |
1.25 |
0.31 |
2.40 |
0.35 |
0.48 |
0.27 |
0.87 |
0.20 |
0.88 |
|
|
9 |
HOU |
L |
444 |
0.42 |
1.30 |
0.30 |
2.13 |
0.09 |
0.50 |
0.23 |
0.26 |
0.23 |
0.86 |
|
|
10 |
TOR |
R |
311 |
0.40 |
1.07 |
0.32 |
3.00 |
0.93 |
0.47 |
0.32 |
1.63 |
0.16 |
0.85 |
|
|
11 |
ANA |
L |
671 |
0.42 |
1.33 |
0.28 |
1.57 |
-0.45 |
0.44 |
0.21 |
-0.05 |
0.28 |
0.83 |
|
|
12 |
SLN |
L |
126 |
0.42 |
1.38 |
0.26 |
1.29 |
-0.72 |
0.43 |
0.19 |
-0.36 |
0.33 |
0.82 |
|
|
13 |
MIA |
R |
231 |
0.40 |
1.13 |
0.22 |
1.67 |
-0.36 |
0.41 |
0.32 |
1.63 |
0.24 |
0.80 |
|
|
14 |
SFN |
R |
636 |
0.41 |
1.20 |
0.25 |
1.86 |
-0.17 |
0.43 |
0.24 |
0.41 |
0.23 |
0.79 |
|
|
15 |
CIN |
R |
131 |
0.38 |
0.88 |
0.11 |
3.20 |
1.12 |
0.48 |
0.36 |
2.24 |
0.15 |
0.78 |
|
|
16 |
HOU |
R |
145 |
0.37 |
0.74 |
0.37 |
6.50 |
4.31 |
0.68 |
0.21 |
-0.05 |
0.11 |
0.76 |
|
|
17 |
LAN |
L |
844 |
0.41 |
1.20 |
0.31 |
2.06 |
0.02 |
0.51 |
0.18 |
-0.51 |
0.25 |
0.75 |
|
|
18 |
CLE |
R |
783 |
0.42 |
1.27 |
0.31 |
1.72 |
-0.31 |
0.49 |
0.15 |
-0.97 |
0.29 |
0.74 |
|
|
19 |
CHN |
R |
826 |
0.41 |
1.14 |
0.28 |
1.88 |
-0.15 |
0.49 |
0.17 |
-0.66 |
0.26 |
0.69 |
|
|
20 |
CLE |
R |
297 |
0.39 |
0.96 |
0.31 |
1.55 |
-0.47 |
0.36 |
0.30 |
1.33 |
0.23 |
0.67 |
|
|
21 |
ANA |
R |
398 |
0.39 |
0.91 |
0.27 |
2.83 |
0.76 |
0.55 |
0.21 |
-0.05 |
0.19 |
0.63 |
|
|
22 |
ATL |
L |
256 |
0.36 |
0.56 |
0.37 |
4.20 |
2.09 |
0.54 |
0.33 |
1.78 |
0.13 |
0.61 |
|
|
23 |
KCA |
R |
1222 |
0.39 |
1.00 |
0.28 |
1.46 |
-0.56 |
0.43 |
0.20 |
-0.20 |
0.30 |
0.59 |
|
|
24 |
CHA |
L |
966 |
0.39 |
0.97 |
0.30 |
1.56 |
-0.46 |
0.45 |
0.18 |
-0.51 |
0.29 |
0.56 |
|
|
25 |
OAK |
R |
686 |
0.38 |
0.87 |
0.26 |
2.68 |
0.62 |
0.55 |
0.17 |
-0.66 |
0.20 |
0.56 |
***For each pitcher, I can add each 'Pitch Score' weighed by usage in his repertoire for his Repertoire Score. If you're interesting in one pitcher relative to another (potential group), you can send me requests via Rotobanter or follow me on Twitter @Rotobanter.
