On 17 Jul 2001 15:23:29 -0700, [EMAIL PROTECTED] (dennis roberts) wrote:
> At 04:08 PM 7/17/01 -0400, Rich Ulrich wrote:
>
> >But, so far as I have heard, the league MEANS stay the same.
> >The SDs are the same. There is no preference, that I have ever
> >heard, for records to be set by half-season, early or late, team
> >or individual. My guess is that association between "talent"
> >and "winning" (or hitting, or pitching, etc.) remains the same.
dmr >
> but, individuals are not half tests ... and, the mean # of homers in the
> second half is not the same (except by coincidence) to the # of home runs
> in the second half ... the original post was not about TEAM stats ... which
> are fixed in the sense that if one team loses alot ... another team wins
> alot ...
I am not at all convinced of a difference.
Sporting statistics still seem to me to be exactly the same
as parallel tests in psychology. Team stats, I agree, might
seem MORE or LESS parallel - more parallel, since the
means have to be the same. But UP for one has to be DOWN
for another.
Exactly like homers, the IQ score in May is not exactly the same as
January, "except by coincidence". If you were scanning a group,
you would expect RTTM in either instance, exactly as described
by the correlation, etc.
dmr >
> every individual player could get better the 2nd half of the season ... or,
> get worse ... in terms of batting ...
[ ... ]
To be sure: I was referring to performance *in* a 2nd half,
and not as statistics that are cumulative.
- History says, a big change is less likely for baseball than
for a psych-test. If you take your parallel IQ test several months
apart, I suppose you could sprain-a-brain in the meantime.
Or drop out of school and miss the test entirely.
You can read in the sports page that a "team has caught fire"
or "is in the slumps." However, so far as I have seen, the
longest streaks are amazingly consistent with chance.
I have seen estimates, for the major US professional sports.
The estimates for individual streaks are not beyond chance, either.
(Some of these were in articles published in the ASA journal
named Chance, over the last several years.)
--
Rich Ulrich, [EMAIL PROTECTED]
http://www.pitt.edu/~wpilib/index.html
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