THE BOOK--Playing The Percentages In Baseball

The alternative hypothesis is that Carlos got it spot on but Hughes is in the 20% or so of below average hurlers who throw a great game that you characterized the other day

We’ll have to wait a couple of months to find out!

I think it’s one thing to discuss the impact of a player’s mechanics on his own body (i.e., how much stress is he putting on himself).  And it’s one thing to say that someone is consistent or not in his motion and release points.

It is quite another to think that you can analyze all these various inputs, and determine a set of outputs (whether you conclude that this pitcher will be injury free, is a good pitcher, etc).

In terms of analyzing mechanics, it is what it is.  You can describe what they are, and the advantages and disadvantages.  But, to say that if a particular pitcher would change his mechanics or approach a certain way (input) and that this will cause a certain result (output) is quite another.

Will Carroll can say in 2003 that Mark Prior’s mechanics are “perfect”, and it could mean something, or it could not.  And someone can say that Calvin Schiradi had fear in his eyes in 1986.  Unless and until someone actually documents the inputs and outputs of what they are saying, the analysis of mechanics must be limited to inputs.

It’s up to other analysts to look at these inputs, and see if they relate to any outputs.

When I read these mechanics essays, that’s what I do.  I skip over anything that the expert thinks in terms of outputs, and focus strictly on the inputs.

Chill, MGL.  I, for one, find these types of articles interesting.  They are opinion articles, not “science” articles, and I learn a lot by reading them.

Just because something hasn’t been “proven by the scientific method” doesn’t mean that it isn’t interesting or useful.  What if something can’t be proven by the scientific method?  Does that mean we should not ever talk about it?

To add to what studes said, I think we can agree that taking these essays as predictive are problematic.  But science need not be predictive; there is a difference between analysis and synthesis.  In my opinion, our understanding of biomechanics is in the analytical stage, which is why studies such as these are valuable.

This about it this way.  Statheads spent some time figuring out what was important when it came to scoring and preventing runs, but it took additional work to learn how to predict what ballplayers would do in the future. 

Biomechanical analysis are still in the first stage.  And if it’s frustrating when numbers don’t come out the way we want them, just imagine how difficult it is to experiment via uncontrolled biological observation!

So let’s be patient and see where we are in five years or so.  We might be surprised that stumbling in the dark today might pay off in the future.

And then Hughes got hurt. So maybe his mechanics weren’t good after all?

Oh and on Prior, something to think about - Prior and Wood were subjected to similar workloads. They both broke down. Compare Prior, good mechanics, vs. Wood, bad mechanics. Wood’s injury was much more severe. Anecdotal, but interesting.

Studes: Chill, MGL.  I, for one, find these types of articles interesting.  They are opinion articles, not “science” articles, and I learn a lot by reading them.

But the reason you found it interesting is presumably because you don’t/didn’t know anything about mechanics, and how do you know that you actually “learned” something valuable instead of a steaming pile of crap?

Let’s play a game.  Suppose that there are no statistics in baseball.  Suppose that there are no records kept at all.  Literally no individual accomplishments are written down.  No BB-Ref, no Retrosheet. 

Now, under this system, it would be virtually impossible to really know which players are more valuable than others, unless you watch every single game and have a flawless memory.  So what do you do? You rely on the experts and their opinions.  You judge who the best players are by listening to what Steve Phillips says or John Kruk or Joe Morgan or whomever. 

So you go to ESPN.com and you read an article by Steve Phillips that explains why Scott Podsednik is more valuable than J.D. Drew, or something.  What do you think of that? Well, since no records are kept you just have to take his word for it, don’t you? After all, he’s the expert.  Someone like MGL might question Steve Phillips, and then you would respond with, what? With:

Chill, MGL.  I, for one, find these types of articles interesting.  They are opinion articles, not “science” articles, and I learn a lot by reading them.

In other words, it’s an interesting opinion article only if it’s true.  It could be a big pile of bullshit and you would never know, but you think you learned a lot because he sure sounds like he knows what he’s talking about…

(My sincerest apologies to Carlos Gomez for indirectly comparing him with Steve Phillips.  I also have no disrespect for Gomez’s work, but I am a skeptic by nature.)

I’m not trying to be combative at all (IOW, no reason to “chill").  I am in agreement with El Ryan and I’ve mentioned it before on BTF. I simply have no idea whether anything that Carlos or Will says has any merit whatsoever other than the “observations” themsleves. I think one has to be very careful about putting too much (or any for that matter) stock in something just because it “sounds good.” The world is filled with scams and charaltans who “sound good.” Just watch all the infomercials on late night TV and the commercials on talk radio and on Fox News.  I am not suggesting that Carlos et. al are charlatans, but I have not seen ANY evidence one way or another.  I don’t know what else to say.

I don’t quite understand the gripe.  Isn’t what CBW and others do a lot like Johnny Miller or someone like that looking at a golf swing after the pro blocks the ball out into the lake on the 18th?  They’re looking to see why certain outcomes happen.  That said, is it even possible to look at someone’s mechanics and predict what’s going to happen?  Extending the golf analogy, if you looked at Chi Chi Rodriguez’s swing, you’d probably predict that he’d have a hard time winning any tournaments (in his prime, of course).  Likewise, there’s a lot of guys in the world with very nice, mechanically sound golf swings who will never win anything.  And again, this is an analogy, and possibly a weak one at that.  And again (again), I just don’t see what kind of predictiveness you could actually want/get from this in the first place.

"His stuff is nasty, but I would worry about his durability.”

I don’t think Carlos was trying to make a prediction here, but that line isn’t too bad in describing a pitcher who threw a nohitter into the 7th inning, left the game with an injury and will miss over a month.

I DON’T have any “gripe.” First of all, I posted this in kind of a fun way, as I thought it was amusing that Carlos talked about Hughes throwing differently this year than last year after “coincidentally” having a few bad starts in 07 and then he throws a no-hitter!  No one else sees the irony in that?

Aside from that I do have an “issue” with these articles about pitching and hitting mechanics.  For one thing, most of what I have read is comparing a pitcher’s or hitter’s mechanics in one time period to another.  Do we have ANY idea whether those mehcanics perhaps change from day or day or even pitch to pitch?  Just because some guy shows me some frames from one year and they appear to be different from some frames from another year doesn’t convince me of squat, let alone that the one set of mechanics represents a “norm” for one year and the other for another year.  And it always seems to be AFTER the fact.  So-and-do is hitting worse than last year, so they show a few frames of a swing from this year and from last year, and they go on about how different it is.  How do I know that any idiot can’t find plenty of “good” and “bad” AB’s from ANY year?  And how do I know that one set of mechanics is better than another?  Because some huy tells me that his “hands stay together longer.” How do I know that is good?  Maybe throwing from different arm slots is GOOD?  Maybe having a consistent arm slot is better?  Maybe ALL pitcher’s arm slots vary from pitch to pitch.  Do we know the answers to any of these things?  Etc.

And what is the point of ANY analysis if it doesn’t tell us SOMETHING?  The analysis that they are doing in terms of “describing” the biomechanics may be spot on, but if it has no predictive ore correlative value in terms of success or injury, then WHAT IS THE POINT?

To give a concrete example, as Rally mentioned, Carlos thinks that Highes mechanics may not be conducive to a healthy future.  Do we have ANY evidence that that is true (that his type of mechanics correlate with a higher than average chance of injury), other than a former minor league pitcher said so?

And yes, half the time when Johnny Miller talks about golf swings, it is yada, yada, yada with him too, although I don’t really want to bring him and golf into the picture.  And BTW, there are many, many theories on golf swings, and I have never seen any scientific evidence that one is better than the other.  And I play a lot of golf and read a lot of golf magazines.  So maybe golf is a GOOD analogy.

Two things:

(1) Mickey, I have already talked to Carlos about doing such a study. We won’t have any results for almost two years, but hey, there’s a long wait involved when you’re looking to see if your predictions come true.

(2) Until then, why don’t you just read Carlos’s articles as descriptive rather than prescriptive? If you don’t want to put any stock into Carlos’s opinions on a pitcher’s mechanics, at least look at the things he points about about that pitcher’s mechanics. They’re still things you wouldn’t have noticed, and the articles are fascinating either way.

Maybe it is just me, and again, I have nothing against Carlos, Will, et al., and the field in general (biomechanics or whatever it is called), but those articles and descriptions do nothing for me whatsoever.  But then again, WPA does nothing for me as well, and Tango and others seem to love it.

To some extent, I am on a lifelong crusade to rail against phony “industries.” For example, mutual funds and brokerage houses are 100% (OK 99%) phony industries, yet millions of people and the media treat it/them as if they are science. Not only are they not science, they have almost no merit whatsoever, and the financial pundits might as well be speaking Peanuts-ese (what the adults in the Peanuts cartoons sound like). I don’t know if this field is the same, but it might be.  I’m willing to bet that much of it is.  Anytime you have non-scientists (define that however you want) speaking off the top of their heads, regardless of how erudite they sound, all of my warning bells go off.

Hey, if you don’t want to wait two years, go back and show Carlos some old videos of players with their faces and teams blocked out or something like that.

I am just a born (or learned) skeptic, which I think in most cases is appropriate if you are interested in the learning the “truth.”

I think I come down somewhere between MGL and DSG/Studes. I accept the predictive/descriptive distinction, but like MGL, I don’t think we yet have evidence that these analyses are even describing anything that matters.  I don’t agree with MGL that we should demand demonstrated predictive power before taking these analyses seriously.  But I do think it’s fair to ask for some kind of evidence—not necessarily conclusive—that it is in fact descriptive. 

For example, the kind of post-hoc analysis MGL describes really doesn’t tell us anything.  But suppose an analyst says something like this:  “I carefully reviewed a random sample of 15 starts by this pitcher in 2002, and a random sample of 15 starts in 2005.  The pitcher’s leg kick was 6” higher on average in 2005, and his component ERA was 1.00 lower that year.” Does that prove the leg kick made the difference?  No, but it’s suggestive, and a legitimate form of evidence.  And if the analyst went on to look at other pitchers, and found they too pitched better when employing similar mechanics, I’d be even more impressed.  And the kind of blind test MGL mentions—which I also suggested in an earlier BTF thread—would also give us evidence that these analysts can perceive things that matter.

Maybe I’m wrong, but I don’t think we’re seeing much or any of that kind of analysis yet.  We should, and it doesn’t require a 2-year waiting period.

I appreciate reading what a baseball professional thinks about mechanics and deliveries.  I also enjoy reading editorials in the New York Times.  And I enjoy reading different accounts of what’s gone wrong in Iraq.  I even enjoy reading different theories of what works in the stock market.  I appreciate the stimulation and opportunity to look at something differently.  I don’t need “hard science” to find it worthwhile.

To me, that’s what people like Carlos and Will are doing.  Asking for more research in the subject is a great idea, but I wouldn’t disparage what’s currently being done.

Post from David A:
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I’m not exactly well-read in the field, but there have been accessible scientific studies done on what happens to the body during the pitching motion (http://www.lookoutlanding.com/story/2007/4/30/22305/2308). Also, I seem to recall that Japanese researchers have been studying pitching biomechanics for a LONG time, since before Mike Marshall, even. To sum up, there is plenty of information out there, enough to make cautious predictive statements, I gather, since there is available data on what sorts of forces the body endures in various pitching motions, and which parts of the body are more susceptible to injury.

I thought of the consistency of motions issue, too, and that’s something that we kind of have to trust analysts on, that they’ve selected information that’s representative. However, in a world in which we can track baseballs and bodies all over a ballfield, and in which we have high speed video to analyze, showing how a body motion increases injury risk or whether or not a motion is as efficient or powerful as it could be should be within somebody’s grasp.

Milb.tv offers video as far back as Spring of 2005. If someone is really interested in this, it shouldn’t be too difficult to arrange a quasi-experimental study where you find a few dozen clips of somewhat obscure pitchers who experienced injuries or stayed healthy during the second half of the season and see how well observers can predict these kinds of outcomes.

I would be surprised if some MLB teams haven’t already done something like this, but then again I’m often surprised at what MLB teams do and don’t do.

Top blogger Jeff Sullivan provides us with la link to actual resources:
http://www.lookoutlanding.com/story/2007/4/30/22305/2308

(Hat tip: studes)

MGL-

You imply that I want him to change back to his old mechanics because he had a poor MLB debut.  In his Futures game appearance, he gave up 3 runs on 4 hits in one inning. If anything, people should say “he wants him to go back to that when he got bombed?” YES. His MLB debut is a 1 game sample, results be damned. Come on dude, you know better than that.

Carlos, aka ChadBradfordWannabe

edit: my above post should say ‘spring of 2006’, not 2005.

Oh, and a sneak peak into my follow-up article at THT. This is his MLB debut vs his start 2 days ago…

(click on my name)

Carlos, my comments on Hughes and your analysis are somewhat toungue in cheek, but there is indeed a human bias towards wanting to find out what is “wrong” or “right” with someone or something after a small sample of performance whether there is any causative relationship or not.

I really like Jeff’s article referenced above, and not because he agrees (somewhat) with my general opinion on the matter.

Also I must admit that I have not paid much attention to the Gomez and Carroll articles and that I will go back and re-read them and consider my stance again.

Admin note: for those posting links, like Carlos did in post #21, they sometimes get flagged as spam.  So, if you don’t see them, don’t worry.  I check my logs periodically, and will unflag them.

Silver, I moved all the investing topics to here:
http://www.insidethebook.com/ee/index.php/site/comments/forecasting_stocks/