from Amazon
Tuesday, September 18, 2007
Fundamental Pitch Count
How to refine pitch counts? This is what I think:
and the following comment was put in Mike Pagliarulo‘s blog:
I am a huge Bill James proponent, but I definitely appreciate what I think is the basic motivation behind FPC (or Fundamental Pitch Count, if acronyms are a no-no).
The way I approach the pitch counts is to tag each pitch on a scale from 0 to 2, in terms of “stress”. Seeing that I am not a scout, I would give out a flat 0.4 for a knuckler, 0.8 for a fastball, 1.6 for a curveball, etc. Perhaps for a Randy Johnson, a fastball would only be 0.7, and for Wakefield (when he throws one) would be a 0.9. The basic idea here is that there’s as much stress in throwing 120 fastballs as there is in throwing 60 curve balls. Whether I’m right in the actual numbers, I have little idea. But, that’s the basic framework.
What it sounds like what pags and MOB are doing is something more refined, and looking at each pitch one at a time, looking at their mechanics for each pitch. If this is their approach, then I applaud them, and would appreciate seeing something written about it, prior to it being defended (or ripped upon).
If it’s not their approach, then a bit more info would be appreciated.
I think there’s a ton of thought that would need to go into those stress assignments. For example… I think you’re selling Wakefield short with the knuckleball rating. I cannot throw a baseball more than 55mph, and I’m a reasonably-sized adult who lifts weights (though I always did have a girly arm in little league). He throws the knuckler ideally around 69mph. It looks effortless, but I think it takes a tremendous effort.
I’d think a changeup should have the same stress rating as a fastball, right?
With the mlb.com pitch fx data, you have a tremendous resource for this. I’m less interested in the type of pitch as I am the standard deviation of it’s velocity. Schilling’s been around 89-91mph with his fastball, but threw one in there at 95mph the other day, in the 7th or 8th inning. I’d think that’s got to be the most stressful pitch he threw all day. I’d suggest using standard deviations of velocity, with some kind of multiplier (or degree-of-difficulty) for pitch type and inning. But that’s just my gut guess at what I’d do.
The other thing, which none of us can measure, is the sort of inherent stress. 1999 Pedro, at 5’10”, 155lbs, throwing 97mph, has got to be almost infinitely more stressful than Randy Johnson throwing that hard. Likewise, Fenway in October has got to be tougher on arms than Texas in July. Fascinating stuff.