Monday, September 27, 2010

YOU CAN'T HIT WHAT YOU CAN'T SEE: On Saturday, a former communist snuck into a California border town and threw a hard object at 105.1 miles per hour, narrowly missing a clergyman. He threw a bunch of other hard objects too, every one at more than 100 miles an hour. One of the intended victims managed to fight the ex-communist off with a stick, nobody was hurt, and the ex-communist left, defeated.

The ex-communist was Aroldis Chapman, a Cuban emigre; the hard object was a baseball; the clergymen were of the San Diegan Padre order. So, really, the only significant things about the encounter were the 105-mile-an-hour pitch -- the fastest ever reliably recorded -- and the snare-beat consistency of all of the 100-mph pitches.

A few weeks ago, when Chapman made his MLB debut, Jeff Sullivan at Lookout Landing did a couple of posts looking at how velocity affects the hittability of pitches and how hitters do against 100-mile-an-hour pitches. The results of the first confirmed the obvious -- the faster the pitch, the harder it is to put your bat on it. But the interesting thing to me was that of over 550 pitches thrown at greater than 100 miles an hour in the sample period, there were zero home runs. Chapman throws so hard that he has eliminated a True Outcome.* That's scary.

*The "Three True Outcomes" -- strikeouts, walks, home runs -- are the three principal things that can happen during a plate appearance that are not affected by the defense. Since the difference between a deep fly ball and a home run is sometimes luck, some key pitching stats try to normalize the ratio between the two, but maybe that would be unfair to Chapman and Joel Zumaya.

12 comments:

  1. Joseph J. Finn6:02 PM

    "<span>*The "Three True Outcomes" -- strikeouts, walks, home runs -- are the three principal things that can happen during a plate appearance that are not affected by the defense. "</span>


    Waaaaait a second, I'm going to mildly object to this, unless there's more to it.  A strikeout is always affected by the defense, by how the pitcher throws it and the catcher calls the pitch.  A walk, I assume we're excluding intentional walks, but can be affected by how the pitcher misses the plate.  Home run, I'll go with on being not especially affected by the defense.

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  2. isaac_spaceman6:38 PM

    "Defense" typically is defined as run prevention minus pitching contribution.  To the extent you are using "how a pitcher throws it" to mean the quality of the pitching -- fast, slow, straight, breaking, etc. -- that's the point.  The idea of defense-independent pitching statistics (DIPS) is that we want to filter out all of the variables that occur after the pitcher lets go of the ball, so that we can make judgements about the quality of what happens before the pitcher lets go of the ball. 

    It is certainly true that what pitches the catcher calls affect the outcome.  For the purpose of DIPS, we treat that as part of the act of pitching, not part of the act of defense.  It probably doesn't matter over the long haul, since all of the evidence is that catcher ERA is not a repeatable skill.  That suggests that while a catcher may call a good game or a bad one (or a good pitch or a bad one), that's essentially a random variable that, at least theoretically, should regress to the mean over a large enough sample.   

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  3. Reading the first few sentences of this I initially thought it was about a scene from last night's "Eastbound and Down" I somehow missed.

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  4. girard317:00 PM

    Seeing how Zumaya has had nothing but health problems since consistently throwing over 100mph, I would have to think that it may not be possible to sustain that velocity over long periods. Although many say Feller could toss over 100 and he lasted a while.

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  5. Chapman v. Utley-Howard-Ibanez is going to be fun, should it happen.

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  6. Shorter Isaac: "By defense, I just mean the fielding."

    DIPS is one of the most amazing advances in baseball analysis.  The idea that a pitcher can't really control for what becomes an XBH, versus single, versus out (absent extreme cases) has powerful applications.

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  7. isaac_spaceman8:23 PM

    It's not just the fielding, because it also includes the throwing. 

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  8. Well, by "fielding" I meant "the handling of balls in play by the fielders, not just the catching."  Agreed?

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  9. isaac_spaceman10:10 PM

    Yes, but if we need to define terms to define terms, we might just as well say "defense"

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  10. isaac_spaceman10:13 PM

    or "everything after the pitcher lets go of the ball"

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  11. Adam C.11:47 PM

    So did Nolan Ryan. 

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  12. Anonymous12:23 PM

    So, did isaac inspire on of Ken Jennings' questions this week? The world wants answers.

    --bd

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