http://www.princeton.edu/~mdaniels/PD/PD.html describes this WorlD as quoted below, and implements the GoldenRule, BrazenRule and IronRule. There are also more complex heuristics for this game, and GeneticAlgorithms have been applied in generating them too. Prisoner's Dilemma@Everything2.com has in-depth info.
The prisoner's dilemma was originally formulated by mathematician Albert W. Tucker and has since become the classic example of a "non-zero sum" game in economics, political science, evolutionary biology, and of course game theory.A "zero sum" game is simply a win-lose game such as tic-tac-toe. For every winner, there's a loser. If I win, you lose. Non-zero sum games allow for cooperation. There are moves that benefit both players, and this is what makes these games interesting. In the prisoner's dilemma, you and Albert are picked up by the police and interrogated in separate cells without a chance to communicate with each other. For the purpose of this game, it makes no difference whether or not you or Albert actually committed the crime. You are both told the same thing: If you both confess, you will both get four years in prison. If neither of you confesses, the police will be able to pin part of the crime on you, and you'll both get two years.
If one of you confesses but the other doesn't, the confessor will make a deal with the police and will go free while the other one goes to jail for five years. At first glance the correct strategy appears obvious. No matter what Albert does, you'll be better off "defecting" (confessing). Maddeningly, Albert realizes this as well, so you both end up getting four years. Ironically, if you had both "cooperated" (refused to confess), you would both be much better off.
In 1980, political scientist Robert Axelrod of the University of Michigan in Ann Arbor held a tournament in which he invited game theorists to submit strategies for repeated prisoner's-dilemma encounters. The computer-simulated tournament produced a surprise: The hands-down winner was one of the simplest strategies, a tit-for-tat rule.(...)
The difference between the games' outcomes arises because in the snowdrift game, but not in the prisoner's dilemma, it's in a player's best interest to be the opposite of his neighbors.
so SnowDrift might be interesting to explore, as also here a basic thing is ProxemicS
Nature. 2004 Apr 8;428(6983):643-6. Spatial structure often inhibits the evolution of cooperation in the snowdrift game.
biologists have explored a continuous variation:
J Theor Biol. 2005 Jan 7;232(1):99-104. The iterated continuous prisoner's dilemma game cannot explain the evolution of interspecific mutualism in unstructured populations. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WMD-4DBSV6T-2&_coverDate=01%2F07%2F2005&_alid=414796014&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=6932&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=ec884d61e3887ead81d6eb82e9c06b78
J Theor Biol. 2004 Nov 7;231(1):97-106. Effects of neighbourhood size and connectivity on the spatial Continuous Prisoner's Dilemma. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WMD-4D1V7M9-1&_coverDate=11%2F07%2F2004&_alid=414795934&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=6932&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=b6f3392c1524fbe148c26b03f506df61
SelfOrganization --antont, Sun, 18 Jun 2006 09:43:36 +0300 reply
just drifted back to reading some of that from here
being --antont, Mon, 31 Jul 2006 17:15:05 +0300 reply