

Understanding the hot hand, the myth of the hot hand, and the myth of the myth - arch_stanton
http://andrewgelman.com/2014/08/12/understanding-hot-hand-myth-hot-hand-time/

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mojoe
Here's some context:

[http://en.m.wikipedia.org/wiki/Hot-
hand_fallacy](http://en.m.wikipedia.org/wiki/Hot-hand_fallacy)

~~~
ChuckMcM
Except the argument in sports is exactly this:

    
    
       > Athletes are not machines, and anything that can 
       > affect their expectations (for example, success in 
       > previous tries) should affect their performance—one 
       > way or another. To put it another way, there is little 
       > debate that a “cold hand” can exist: It is no surprise 
       > that a player will be less successful if he or she is 
       > sick, or injured, or playing against excellent 
       > defense. Occasional periods of poor performance will 
       > manifest themselves as a small positive time 
       > correlation when data are aggregated.
    

Basically the question of what factors could be present that would increase
the success likely hood of a basketball scoring attempt, and then whether or
not those factors can persist over time or if they are always just noise. And
the myth part being that someone who believes they will be successful is more
likely to succeed than someone who has no expectation of success.

The science then is can the expectation help, and if so can it bias success in
a statistically significant way.

------
finnh
> (3) not every streak is a hot streak, so the real infrequent, but persistent
> hot hands get diluted;

no true scotsman would have a not-hot streak.

~~~
aetherson
On a purely mathematical level, though, you can see how this could be true.

Like, take basketball out of the equation. Let's say I code up a button. When
you press it, it shows a screen that says "You scored!" or "You failed to
score. :(" Now, I code the button to generally say "you scored" 1/2 of the
time, and "you failed to score :(" 1/2 of the time. But I also code it to say
that on 1% of all scores, it enters a "hot streak" mode where for the next ten
button presses, it's 80% likely to score.

We would agree, yes, that this button has hot streaks?

But now suppose that you look across a large dataset for periods of ten button
pushes in which more than 7 of them are scores. Those are streaks of scores.
Some of those are going to be because the button is in hot streak mode. But
some of them are just going to be because the normal 50% chance clustered.

Now, is my button anything like a good model for how basketball works? I have
no idea. But the sentence "not all streaks are hot streaks" is not self-
evidently crazy.

~~~
Terr_
Or to pick at the semantics a bit: Not all streaks indicate causality. Some
are random artifacts.

Easy enough to prove by flipping a coin. Streaks naturally happen and should
be _expected_ from randomness.

------
preinheimer
I spent a long part of this article thinking it was about poker.

------
clairity
as with most real world situations, the problem (in my estimation) is that
statistics and the experimental model are not yet sophisticated enough to sort
out the effect, so it's hard to distinguish from random. the statistical model
would likely need many more variables, be non-linear, and measure things (like
emotional positivity) more dynamically and/or accurately than possible today.

for example, my shooting shoulder is chronically injured. if i warm up
properly, i seem to shoot better. is this a psychological effect? a
physiological effect? something else? in game situations, it's hard to isolate
the effect from all the confounding variables. even if you could, you'd need
to measure all the confounding variables to negate them in the analysis.

i suspect a non-logic based "math" will have to be developed (quantum
computing?) before we can understand these kinds of situations.

------
diminoten
It appears academics argue much like folks on the Internet argue, just with
different vocabulary and maybe a touch nicer.

