Democrats are in denial. Their party is actually in deep trouble.

Started by jimmy olsen, October 19, 2015, 10:15:51 PM

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Eddie Teach

Quote from: frunk on October 21, 2015, 02:59:59 PM
You are missing Level 5:

It may or may not be biased, but I can guarantee some idiot is going to attach far too much significance to the predictive power of 10 flips of a coin.

:D
To sleep, perchance to dream. But in that sleep of death, what dreams may come?

The Minsky Moment

It would be silly to revise a prior - even minimally based on a 6-4 split a 10 flips.  A 6-4 split is exactly the kind of result one would expect to see if a fair coin is flipped 10 times.
The purpose of studying economics is not to acquire a set of ready-made answers to economic questions, but to learn how to avoid being deceived by economists.
--Joan Robinson

frunk

Quote from: The Minsky Moment on October 21, 2015, 03:06:41 PM
It would be silly to revise a prior - even minimally based on a 6-4 split a 10 flips.  A 6-4 split is exactly the kind of result one would expect to see if a fair coin is flipped 10 times.

In fact a 6-4 split favoring heads or tails is more likely than the perfect 5-5.

DGuller

Quote from: The Minsky Moment on October 21, 2015, 03:06:41 PM
It would be silly to revise a prior - even minimally based on a 6-4 split a 10 flips.  A 6-4 split is exactly the kind of result one would expect to see if a fair coin is flipped 10 times.
It's a very likely result for a fair coin.  But it's an even more likely result for a coin that is head-biased.  Of course your revision of a prior would be extremely minimal (and would depend on your initial judgmental confidence in the fairness of the coin), but the prior should still be revised.

The Brain

Women want me. Men want to be with me.

Malthus

Quote from: The Brain on October 21, 2015, 03:11:12 PM
Are there negative levels btw? I'm asking for a friend.

One guy punches the other in the face and steals the coin. That's -1.  :hmm:
The object of life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane—Marcus Aurelius

Berkut

Quote from: Malthus on October 21, 2015, 03:24:02 PM
Quote from: The Brain on October 21, 2015, 03:11:12 PM
Are there negative levels btw? I'm asking for a friend.

One guy punches the other in the face and steals the coin. That's -1.  :hmm:

But he would claim it was actually Level 6, and only looks like level -1 to you because you are at level 5, and how could you dispute him?
"If you think this has a happy ending, then you haven't been paying attention."

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DGuller

Quote from: DGuller on October 21, 2015, 03:10:12 PM
Quote from: The Minsky Moment on October 21, 2015, 03:06:41 PM
It would be silly to revise a prior - even minimally based on a 6-4 split a 10 flips.  A 6-4 split is exactly the kind of result one would expect to see if a fair coin is flipped 10 times.
It's a very likely result for a fair coin.  But it's an even more likely result for a coin that is head-biased.  Of course your revision of a prior would be extremely minimal (and would depend on your initial judgmental confidence in the fairness of the coin), but the prior should still be revised.
But that's a very good example of how you can over-learn some things when getting to classical statistics stage.  A lot of people learn that a small sample size with not unusual outcomes doesn't tell you anything.  That's almost right.  It doesn't tell you a whole lot, but it tells you more than nothing.  Every single coin flip tells you something and should make you update your prior expectation.

PRC

If you flip a coin in the air it has a chance of hitting a bird 50% of the first time you flip it, especially if you're outside. 

DGuller

Quote from: PRC on October 21, 2015, 03:49:44 PM
If you flip a coin in the air it has a chance of hitting a bird 50% of the first time you flip it, especially if you're outside.
Depends on how informed your prior is.

Eddie Teach

Quote from: DGuller on October 21, 2015, 03:52:11 PM
Quote from: PRC on October 21, 2015, 03:49:44 PM
If you flip a coin in the air it has a chance of hitting a bird 50% of the first time you flip it, especially if you're outside.
Depends on how informed your prior is.

The prior knows how many birds are supposed to be there, but doesn't realize the abbot had one of them for supper last night.
To sleep, perchance to dream. But in that sleep of death, what dreams may come?

The Brain

Women want me. Men want to be with me.

garbon

"I've never been quite sure what the point of a eunuch is, if truth be told. It seems to me they're only men with the useful bits cut off."
I drank because I wanted to drown my sorrows, but now the damned things have learned to swim.

frunk

Quote from: DGuller on October 21, 2015, 03:49:19 PM
But that's a very good example of how you can over-learn some things when getting to classical statistics stage.  A lot of people learn that a small sample size with not unusual outcomes doesn't tell you anything.  That's almost right.  It doesn't tell you a whole lot, but it tells you more than nothing.  Every single coin flip tells you something and should make you update your prior expectation.

This type of micro adjustment is only meaningful if there will be no more trials available (meaning no further adjustment is possible) and there will be a really large number of outcomes that will have to be predicted.  Otherwise a later adjustment of the priors will be greatly more significant or the number of outcomes to be predicted will not meaningfully show the difference between the original prior and the changed one.

The Brain

Women want me. Men want to be with me.