The Prisoner's Dilemma

George Costanza

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The Prinsoner's Dilemma is a fundamental problem in game theory that demonstrates why two people might not cooperate, even if it is in both their best interests to do so. Here is the situation:

Two suspects are arrested by the police. The police have insufficient evidence for a conviction, and, having separated both prisoners, visit each of them to offer the same deal. If one testifies (defects from the other) for the prosecution against the other and the other remains silent (cooperates with the other), the betrayer goes free and the silent accomplice receives the full 10-year sentence. If both remain silent, both prisoners are sentenced to only six months in jail for a minor charge. If each betrays the other, each receives a five-year sentence. Each prisoner must choose to betray the other or to remain silent. Each one is assured that the other would not know about the betrayal before the end of the investigation. How should the prisoners act?

OK - Go.
 

Immanuel

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No honor among thieves. Rat the other guy out.

If he's too stupid to do it, then that is his tough luck.

Immie
 
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George Costanza

George Costanza

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No honor among thieves. Rat the other guy out.

If he's too stupid to do it, then that is his tough luck.

Immie

The key to the problem is that the two prisoners are not allowed to communicate with each other prior to giving their answers.

A can certainly rat B out - but A doesn't know what B is going to do, and that makes the critical difference. If A rats B out and B chooses to remain silent (which he can do), A goes free while B gets a 10-year sentence. However, if A rats B out and B rats A out, then they both get 5-year sentences.

So, at the very least, before deciding what to do, A has to give some thought to what he thinks B is going to do.

"Ratting the other guy out" may well not be the best option.

Rational choice leads the two prisoners to both rat the other one out, even though each prisoner's individual reward would be greater if they both played cooperatively.

In truth, this is a horribly complicated puzzle. There are numerous Web sites discussing it. One of the most basic is this:

http://en.wikipedia.org/wiki/Prisoner's_dilemma
 
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JW Frogen

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This is why you have to have Vito waiting on the outside ready to take the guy who ratted out the other guy out on a little boating trip.
 

Immanuel

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No honor among thieves. Rat the other guy out.

If he's too stupid to do it, then that is his tough luck.

Immie

The key to the problem is that the two prisoners are not allowed to communicate with each other prior to giving their answers.

A can certainly rat B out - but A doesn't know what B is going to do, and that makes the critical difference. If A rats B out and B chooses to remain silent (which he can do), A goes free while B gets a 10-year sentence. However, if A rats B out and B rats A out, then they both get 5-year sentences.

So, at the very least, before deciding what to do, A has to give some thought to what he thinks B is going to do.

"Ratting the other guy out" may well not be the best option.

Rational choice leads the two prisoners to both rat the other one out, even though each prisoner's individual reward would be greater if they both played cooperatively.

In truth, this is a horribly complicated puzzle. There are numerous Web sites discussing it. One of the most basic is this:

Prisoner's dilemma - Wikipedia, the free encyclopedia

I understand that, but look at it this way, I have an option of spending 10 years in prison, spending 5 years in prison, 6 months in jail or no time at all.

Figuring the guy that I got busted with is untrustworthy anyway, I figure if I don't rat him out, I'm gonna spend 10 years in prison. So, in order to minimize that possibility, I'm gonna rat his ass out. If he's too stupid not to do so against me, then I get off scott free and he can spend 10 years thinking about what a fool he was.

Immie
 

Defiant1

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No honor among thieves. Rat the other guy out.

If he's too stupid to do it, then that is his tough luck.

Immie

The key to the problem is that the two prisoners are not allowed to communicate with each other prior to giving their answers.

A can certainly rat B out - but A doesn't know what B is going to do, and that makes the critical difference. If A rats B out and B chooses to remain silent (which he can do), A goes free while B gets a 10-year sentence. However, if A rats B out and B rats A out, then they both get 5-year sentences.

So, at the very least, before deciding what to do, A has to give some thought to what he thinks B is going to do.

"Ratting the other guy out" may well not be the best option.

Rational choice leads the two prisoners to both rat the other one out, even though each prisoner's individual reward would be greater if they both played cooperatively.

In truth, this is a horribly complicated puzzle. There are numerous Web sites discussing it. One of the most basic is this:

Prisoner's dilemma - Wikipedia, the free encyclopedia

Let's complicate it a little more: Also arrested is a third man, an innocent bystander who has never seen either of the other two men in his life. He was just in the wrong place at the wrong time. He is maintains silence except to proclaim his innocence.

Now instead of how long they would stay in prison change it to how much money they would pay and you have...............






Obamacare
 

Paulie

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No honor among thieves. Rat the other guy out.

If he's too stupid to do it, then that is his tough luck.

Immie

The key to the problem is that the two prisoners are not allowed to communicate with each other prior to giving their answers.

A can certainly rat B out - but A doesn't know what B is going to do, and that makes the critical difference. If A rats B out and B chooses to remain silent (which he can do), A goes free while B gets a 10-year sentence. However, if A rats B out and B rats A out, then they both get 5-year sentences.

So, at the very least, before deciding what to do, A has to give some thought to what he thinks B is going to do.

"Ratting the other guy out" may well not be the best option.

Rational choice leads the two prisoners to both rat the other one out, even though each prisoner's individual reward would be greater if they both played cooperatively.

In truth, this is a horribly complicated puzzle. There are numerous Web sites discussing it. One of the most basic is this:

Prisoner's dilemma - Wikipedia, the free encyclopedia

You hedge your bet by ratting the other guy out. The worst you can get is 5 years, best is go free. If you remain silent, you stand the chance of getting 10.

It's a no brainer.
 

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