Examining Pitch Type Linear Weights

This is apropos of nothing really, but it's the middle of January and we've got to talk about something...  So, let's take a look at which pitchers threw the most successful pitch types in 2011 according to FanGraphs' pitch value leaderboards.  This metric, "uses linear weights by count and by event and breaks it down by each pitch type so you can see, in runs, the actual effectiveness of each pitch."  The number shown for each pitch type is the cumulative runs saved above average for each pitch type a pitcher throws, the higher the number the better (for a thorough breakdown of how this is calculated, click here).



Fastball:
Ian Kennedy (28.7 wFB)
Cliff Lee (27.0 wFB)
Justin Verlander (25.5 wFB)


Slider:
Clayton Kershaw (22.9 wSL)
Ervin Santana (22.0 wSL)
Madison Bumgarner (17.7 wSL)


Cutter:
Dan Haren (30.5 wCT)
Roy Halladay (19.5 wCT)
Gavin Floyd (15.5 wCT)


Curveball:
Roy Halladay (14.1 wCB)
Wandy Rodriguez (13.6 wCB)
Justin Verlander (11.2 wCB)


Changeup:
Cole Hamels (29.3 wCH)
Felix Hernandez (21.4 wCH)
James Shields (17.7 wCH)


Splitter:
Roy Halladay (10.8 wSF)
Edward Mujica (8.2 wSF)
Ryan Dempster (6.4 wSF)


A cursory glance at these numbers seemingly passes the smell test. For the most part, we see the names of some of the game's best pitchers. I found it a bit surprising that Ian Kennedy was atop the fastball category, considering he's more of a control pitcher than a fireballer, but there isn't anything else very shocking there.  You will notice there is only one relief pitcher on this list (Edward Mujica of the Marlins) which makes sense since this stat is cumulative, and much like pitching WAR, starters have a lot more innings and pitches to accumulate value.  There is, however, another stat on the same page which takes this number and scales it to a per 100 pitch average, which eliminates the inherent bias for starting pitchers.


Fastball:
Mariano Rivera (2.96 wFB/C)
Joel Peralta (2.37 wFB/C)
Joaquin Benoit (1.86 wFB/C)


Slider:
Josh Outman (4.67 wSL/C)
Cliff Lee (4.50 wSL/C)
Jonny Venters (4.48 wSL/C)


Cutter:
Sean Marshall (4.60 wCU/C)
Koji Uehara (4.24 wCU/C)
Javier Lopez (4.03 wCU/C)


Curveball:
Matt Guerrier (3.03 wCB/C)
Roy Halladay (2.39 wCB/C)
Livan Hernandez (2.36 wCB/C)


Changeup:
Ryan Madson (4.61 wCH/C)
Jorge de la Rosa (3.97 wCH/C)
Cole Hamels (3.88 wCH/C)


Splitter:
Jonathan Papelbon (2.09 wSF/C)
Roy Halladay (2.02 wSF/C)
Edward Mujica (1.97 wSF/C)


With these, I used two cutoffs to try and filter out as much small sample size wackiness as possible; a minimum 60 innings pitched and the pitcher had to throw the particular pitch type at least 10% of the time. 


First off, we see a lot more relievers here than on the first list.  It is interesting that Mariano Rivera's fastball is rated the most effective in baseball, not his almighty cutter.  This is probably something of a small sample size issue due to the fact that he only throws it a little more than 12% of the time, but it falls within the arbitrary cutoffs I included and this is my post and I can do what I want, dammit.  Josh Outman may not have the best slider in baseball as is suggested here, but he definitely has the most appropriate last name for a pitcher that I can think of.  Roy Halladay shows up twice on this list as well, for both his curveball and splitter, the scary thing is, he didn't throw a splitter before this year.  Previously, Halladay had three above average pitches in his arsenal (FB, CU, CB) and a mediocre changeup that he didn't throw very often.  This year, he abandoned the changeup and started using a split finger grip and the results were pretty darn impressive.  


Like any stat, pitch type linear weights aren't the end-all-be-all.  You cannot unequivocally say that Ryan Madson has the best changeup in baseball because this metric says he does.  This stat is useful, though, as a way of assessing which pitch a pitcher has the best results with.  You can look at a player page of someone you are unfamiliar with, and see what the pitcher's repertoire is and which pitches help him get outs, versus which pitch is merely a show-me pitch.  It's one of many awesome stats on FanGraphs and another reason why it's a great time to be a baseball fan.