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Re: Basic prisoner's dilemma?

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On 4/18/2011 3:37 PM, Lew wrote:
> ODaniele Futtorovic wrote:
>> Lew allegedly wrote:
>>> - "What is the terminating condition of the game?"
>
>> There must be none. If you're ever in a prisoner's dilemma kind of
>> situation, and know that there are only a limited number of passes left,
>> there is only one viable strategy: betray.
>
> Thank you for those informative answers, but the last one leaves me
> wondering still about the terminating condition of the game. Obviously
> if there's a payout (3/3, 5/0, 1/1), there must be an ending.


The payout in a traditional prisoner's dilemma is 2.5 years in jail if 
the prisoner betrays, and 5.25 years in prison if he doesn't.  That's 
assuming equal chances of his partner in crime choosing to betray or not.

It's 0 years if he betrays and his partner doesn't, or 5 years each if 
they both betray.  Average: 2.5.

It's 6 months if neither betrays, or 10 years if only his partner does. 
  Average: 5.25.


> What
> you've described is that the players cannot know when that ending will
> occur, but surely it must still eventually occur?

The trick is knowing that there are no rounds left.  If you know that, 
then the best strategy at the last round is to betray, because there's 
no way your partner can retaliate.  However, if you and your partner 
both know when the last round is, then you'll both betray.

But if you know that you'll both betray on the last round, then there's 
no incentive to cooperate on the n-1 round.  So betray on that round 
too.  And then for the n-2 round, and the n-3 round, etc.  Until you 
might as well betray on all of them.


> So one of the terminating conditions, or attributes of those conditions,
> is player ignorance. What are the rest?


It's knowing when the rounds terminate that makes the difference. 
Normally, the prisoners don't know how many rounds they'll go through. 
But the rounds do terminate, usually after a fixed number of iterations. 
  But the prisoners don't know, it's "blind," someone else makes that 
determination.


> And I remain curious about game choices other than COOPERATE or BETRAY.
>
> I plan to read up on all this now that the forum has sparked my interest.
>

The Wikipedia article is pretty good.

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Basic prisoner's dilemma? theglazeb <theglazeb@gmail.com> - 2011-04-17 19:51 -0700
  Re: Basic prisoner's dilemma? Lew <noone@lewscanon.com> - 2011-04-17 23:15 -0400
    Re: Basic prisoner's dilemma? Esmond Pitt <esmond.pitt@bigpond.com> - 2011-04-18 13:54 +1000
      Re: Basic prisoner's dilemma? theglazeb <theglazeb@gmail.com> - 2011-04-17 22:08 -0700
        Re: Basic prisoner's dilemma? Peter Duniho <NpOeStPeAdM@NnOwSlPiAnMk.com> - 2011-04-17 23:47 -0700
        Re: Basic prisoner's dilemma? markspace <-@.> - 2011-04-18 00:14 -0700
  Re: Basic prisoner's dilemma? rossum <rossum48@coldmail.com> - 2011-04-18 13:01 +0100
  Re: Basic prisoner's dilemma? Bent C Dalager <bcd@pvv.ntnu.no> - 2011-04-18 13:38 +0000
  Re: Basic prisoner's dilemma? Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2011-04-18 19:22 +0200
    Re: Basic prisoner's dilemma? Lew <noone@lewscanon.com> - 2011-04-18 13:34 -0400
      Re: Basic prisoner's dilemma? Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2011-04-18 21:26 +0200
        Re: Basic prisoner's dilemma? Lew <noone@lewscanon.com> - 2011-04-18 16:33 -0400
          Re: Basic prisoner's dilemma? Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2011-04-18 23:50 +0200
            Re: Basic prisoner's dilemma? Lew <noone@lewscanon.com> - 2011-04-18 18:37 -0400
              Re: Basic prisoner's dilemma? markspace <-@.> - 2011-04-18 15:51 -0700
    Re: Basic prisoner's dilemma? Michael Wojcik <mwojcik@newsguy.com> - 2011-04-19 16:14 -0400

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