
Which Cognitive Bias Is Making NFL Coaches Predictable? - mhb
https://measureofdoubt.com/2017/02/05/which-cognitive-bias-is-making-nfl-coaches-predictable/
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aaron-lebo
Ugh so torn by this.

Very thorough and great statistical work, but it's all arguing against a weak
premise.

 _His insight was that 2nd and 10 disproportionately followed an incomplete
pass. This generated two hypotheses:

Coaches (like all humans) are bad at generating random sequences, and have a
tendency to alternate too much when they’re trying to be genuinely random.
Since 2nd and 10 is most likely the result of a 1st down pass, alternating
would produce a high percent of 2nd down rushes.

Coaches are suffering from the ‘small sample fallacy’ and ‘recency bias’,
overreacting to the result of the previous play. Since 2nd and 10 not only
likely follows a pass, but a failed pass, coaches have an impulse to try the
alternative without realizing they’re being predictable._

The argument boils down to coaches trying to catch the defense off-guard; they
are either alternating to be random or "overreacting".

It may not be that complicated. Coaches hate 3rd and 10 or more specifically
third and long. Analysts emphasize it every game and the reason why is because
at that point there is no randomness. You pretty much have to pass on 3rd and
10 and the defense knows this, not to mention a play that requires ten yards
takes longer to setup than a play which takes four and the defense is already
rushing your QB...

If you have an incomplete pass on 1st and 10, you pass again on 2nd and 10 and
have another incomplete, you're now looking at passing on 3rd and 10: 3 passes
in a row, no time burned off the clock (time of possession is also highly
valued), and no momentum - you've just fucked up on the same play two times in
a row and you've got to run it (well pass it) again.

You run on second down, you'll usually at worst get a yard or two, but you
very well could have a good run and you're then looking at 3rd and 6, third
and 4, situations that open up your playbook a lot.

This might not be the reason coaches do it, but it's certainly a possibility.
They seem to get into an argument of causality when they've got some
interesting correlations. But I just armchair quarterback so don't mind me.

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WillPostForFood
If the fear of 3rd and 10 was the main factor, then you wouldn't see such an
uneven distribution based on whether the 2nd and 10 came via incomplete pass,
or run for no gain.

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mwfunk
The difference is if a pass fails, you gain nothing, whereas even a mediocre
run will probably give you at least a couple yards. So, if your goal is to
avoid 3rd and 10, a run is more likely to accomplish this than a pass, even
though a successful pass has a much higher ceiling in terms of yards gained.

~~~
WillPostForFood
Yes, I agree, but later in the article they show that if the second and 10 is
due to a run on first down, they are more likely to run on second down than if
they passed on first down. I.e., the coaches are looking backwards not
forwards when they make the decision.

~~~
tossaway1
> they show that if the second and 10 is due to a run on first down, they are
> more likely to run on second down than if they passed on first down

I think you got this backwards. If the first down was a run, they were far
less likely to run on second down compared to when the first down was a pass.

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socrates1998
Man, I am working on a project just like this, but with high school teams.

The problem is that these guys seem to lack how coaches make decisions when
calling plays.

I have a few problems with their research:

1) There are A LOT more variables that go into coaching decisions. They picked
QB completion percent as the one they correlated. This is just a way over
simplification of the process.

2) They applied their findings on the whole league to an individual coach.
They is too much variance between coaches that you just can't do this and be
sound.

3) Even if they are right 90% of the time, this may not even be good enough.
Football plays are sort of like no-limit poker. Any one play can determine a
game. So, if you are wrong 10% of the time, this still may result in giving up
a touchdown because you relied on the probability that they would pass/run the
ball.

4) Coaches are humans and they can very readily make adjustments to their
biases. I have seen it myself when coaching. A coach realizes he has called
55% of his plays to the right, so he ends up calling the next few plays to the
left. All these tendencies are shown to coaches every week, as a result, they
work very hard to counter act their own tendencies.

For me, more promising is using their anti-biases against them. In a truly
random pattern, seeing a run of five plays to the Right isn't that unusual.
However, in football play calling, you won't see this nearly as much as you
think you would.

That's my idea. I am still working on the math, but it might take awhile to be
usable.

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driverdan
> All signs point to the recency bias being the primary culprit.

Saved you a click.

