From: roger@crux.Princeton.EDU (Roger Lustig)
Subject: Re: <None>
Originator: news@nimaster
Reply-To: roger@astro.princeton.edu (Roger Lustig)
Organization: Princeton University
Date: Wed, 9 Sep 1992 03:28:12 GMT

In article <1992Sep8.131825.856@ccsvax.sfasu.edu> z_copeab@ccsvax.sfasu.edu writes:
>In article <5461@blue.cis.pitt.edu.UUCP>, genetic+@pitt.edu (Dr. Dave) writes:
>> Thus spake z_copeab@ccsvax.sfasu.edu:

>>>In article <5440@blue.cis.pitt.edu.UUCP>, genetic+@pitt.edu (Dr. Dave) writes:
>> 
>>>> Thus spake 91287041@ramsey.cs.laurentian.ca (Roger Maynard):
>> This was the point of my comment about tossing 200 coins.  If you toss one
>> coin 102 times, we have a very good idea of what constitutes surprising vs.
>> non-surprising numbers of heads to observe.  On the other hand, if I toss
>> 200 identical coins 102 times each, do you have any feel for how many heads
>> you should expect to see from the coin that comes up heads most often, even
>> if all the coins are fair?  I doubt it; I certainly don't.  There is a branch
>> of statistics that deals with these questions, though; I'll try to post a
>> quick summary of relevant results sometime soon.

>	Sounds like some pseudo-mathematical mumbo-jumbo to me. 

Not to me, but then, I've actually studied statistics.

>Are you really
>saying that batting with the bases loaded is as random as flipping coins? I

Are you really saying that, given a sequence of hits and outs, and a sequence
of heads and tails with a weighted coin, you could tell one from the other?

We have *started* with the null hypothesis that there is no special
"bases loaded" effect that makes Pat Tabler hit better in those cases.
We are looking for evidence to the contrary, and have not found it.  
Random sequences of events could be responsible for his statistical
anomaly.

>should have been clearer on what I meant. Saying a guy has a .500 BA with the
>bases full doesn't mean much when he has only 10 AB. On the other hand, if he
>has 100 AB, it means more, because some of the random fluctuation can be taken
>out, and you get a truer picture of how a batter hits in such a situation,
>since he has sustained his performance over a longer duration.

a) We knew that.  Standard deviation decreases with the square root of
the number of trials.  

b) Thus, we know *how much* more it means.

c) But we must also count in the fact that we looked over hundreds 
of split stats in order to find one as outlandish as Tabler's bases-
loaded number.  This means that the odds of finding one split that big
are much higher than if e'd just looked at one particular player to 
start.  After all, if it were Molitor or Guillen or anyone else, we'd
 be just as impressed.

d) Even with 100 AB, the split is not sufficiently large to make it
very unlikely that this is not the result of a chance operation.

>        Well, if the greed of the players, owners, and little kids who collect
>baseball cards for profit rather than fun don't destroy the game, statheads
>like you will. When you start expecting people to know advanced statistics,
>quantum physics, and tarot card reading to properly understand baseball, you
>have gone too far. 

Huh? It's people like YOU, who think that knowing that Pat Tabler has
hit .500 or whatever with the bases loaded is important to baseball,
who are destroying the game with trivial BS.  If nobody knew that,
would the game be any different? 

Nobody expects fans to know advanced statistics, which this isn't --
it's simple common sense.  Split stats are mostly drivel intended to
give announcers something to say between pitches.

>Why can't you just accept that Tabler, over most of his
>career, has been an excellent hitter with the bases loaded?

Who says he wasn't?  What we're asking is: who cares?  What does it
mean to his next AB, to his team, or to baseball?

> I'm not saying he
>still is, or that he belongs in the HOF because of it.

Well, what ARE you saying?  What's this knowledge worth?

>>>	Also, are you saying that it is impossible for someone to be very good
>>>at one thing, especially if the one thing he is good at he is much better than
>>>other players? 

>> No, but I do suspect that it's impossible to be very good at one thing, and
>> yet quite mediocre at very similar things.  As Roger said, if Tabler's so damn
>> great with the bases loaded, why isn't he at least pretty good with men on
>> first and second, or second and third?  If it's a mental thing, then mostly
>> I would conclude that Tabler is "choking" in 99% of his PAs...

>	Tabler (as of 1990) was hitting about .265 with the bases empty, .310
>with runners on, and about .322 with runners in scoring position. Considering
>that his career batting average was around .275 at the time (I might have to
>check this again), that's a pretty good jump in batting average (by
>comparision, the average player in 1990 hit about 10 points higher with
>runners in scoring position). Tabler *does* hit well with runners in scoring
>position, about 50 points over his career batting average. 

OK, fine.  Now, given that he does that well in ALL Risp situations, is
his bases-loaded stat indication of an additional effect (conceding a
RISP effect for sake of argument; I suspect a runners-on effect would be
easier to prove)?  The numbers say no.

Roger