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Shouldn't the real life examples include, you know, the actual scenario on which the original PD is based? like prosecutors/cops and suspects in, eg, the US legal system? — Preceding unsigned comment added by 188.8.131.52 (talk) 01:14, 6 April 2014 (UTC)
In real world, there is probability the criminal gang would retaliate against the betrayer who was set free at partner's expense.
First, no one expects the real world example to fit the model perfectly; it's an approximation. Second, this deviation from the model you mention isnt essential to the OP's scenario (it might not be gang-related, witness protection etc). Third, the retaliation might not offset the incrementally better sentence from snitching. I think the OP has a point. "Prisoner's dilemma" doesn't seem like one of those labels that's a complete misnomer; it could turn up in cases of actual prisoners in a given legal system. Snarfblaat (talk) 00:32, 5 November 2014 (UTC)
I think the real-life example around "guppies" and tit-for-tat is from Axelrod & Hamilton: http://www.life.umd.edu/faculty/wilkinson/BIOL608W/Axelrod&Hamilton81.pdf They don't metion "guppies", per se, and I don't even know if that species of fish exhibit this behavior, so I didn't make the citation myself. The relevant part of the paper, following an overview of tit-for-tat is "Another mechanism to avoid the need for recognition is to guarantee the uniqueness of the pairing of interactants by employing a fixed place of meeting. Consider, for example, cleaner mutualisms in which a small fish or a crustacean removes and eats ectoparasites from the body (or even from the inside of the mouth) of a larger fish which is its potential predator. These aquatic cleaner mutualisms occur in coastal and reef situations where animals live in fixed home ranges or territories (4, 5). They seem to be unknown in the free-mixing circumstances of the open sea." However, this paper is cited by Morton D. Davis of a real-world example of tit-for-tat by fish cleaning parasites off predators in "Game Theory: A Nontechnical Introduction" ISBN 0486296725Tearaway (talk) 20:57, 14 February 2016 (UTC)
The cause of the apparent dilemma in people's actions
Actually, the one-round prisoner's dilemma is ONLY a dilemma if the agents are completely self interested. Altruistic rational agents in a one-round prisoners dilemma would both chose normally to cooperate.
Let the players be A and B. As both are altruistic, they value their (shared) payoff as the sum of all involved payoffs. Also adopt the form discussed, where -1 is the mutual cooperation payoff, 0 is the defect-while-opponent-cooperates payoff, -3 is the cooperate-while-opponent-defects payoff and -2 is the mutual defection payoff.
Now, if B defects, examine A's choices. If he defects, the total payoff is -4, whilst if he cooperates, the total payoff is -3. If B cooperates and A defects, the total payoff is -3, while if A cooperates the total payoff is -2. So whatever B does, an altruistic player is better off co-operating.
As in the real world players are likely to be a mix of self-interested and altruistic, this explains the mix of outcomes given when people attempt to test the prisoner's dilemma. Consider adding this to the 'Prisoner's Dilemma' main page. — Preceding unsigned comment added by Anticontradictor (talk • contribs) 01:06, 8 December 2015 (UTC)
I feel as if this has been used extensively in storytelling over the decades since it was developed, and likely even before that. However, the example that I thought of as soon as I read the article is the ferry boat scene from The Dark Knight. In this scene, there are two ferries that have sailed from Gotham, one full of everyday commuters and the other full of prisoners from the city jail. Mid-crossing the power to both ferries is cut and the Joker explains that both ferries are wired to explode. Each ferry has a detonator for the other ferry. All they need to do is use it, destroy the other ferry, and they will be saved. In the film both sides decide to not detonate the bombs, trusting the other passengers in the other ferry to do the same. Unless I see any objections to this use of the Prisoners Dilemma I will add it to the page in a couple of weeks. Editengine (talk) 01:32, 9 February 2016 (UTC)
Added the storytelling section. Editengine (talk) 12:46, 18 February 2016 (UTC)
Dr. Duffy has reviewed this Wikipedia page, and provided us with the following comments to improve its quality:
A rambling mess. No mention of dominance, Nash equilibrium or the uniqueness of the Nash equilibrium in the game form.
"A very narrow interpretation rationality" is a weak, subjective statement. Indeed rationality in the context of this game is not defined but simply involves each player playing a best response to the payoff incentives of the game.
We hope Wikipedians on this talk page can take advantage of these comments and improve the quality of the article accordingly.
Dr. Duffy has published scholarly research which seems to be relevant to this Wikipedia article:
Reference : John Duffy & Huan Xie, 2012. "Group Size and Cooperation among Strangers," Working Papers 12010, Concordia University, Department of Economics.