| rdfs:comment | - The prisoner's dilemma
- The prisoner's dilemma was a theoretical problem used in game theory, which demonstrated how cooperation, or a lack of it, could affect the outcome of a situation. If two prisoners were separated and each was given the opportunity to betray his accomplice, there were several different outcomes depending on what each decided and what his accomplice did. Dr Judson had a logic diagram of the prisoner's dilemma on the blackboard in his office at Maiden's Point. The Seventh Doctor recognised it immediately, which enabled him to break the ice with Judson. (TV: The Curse of Fenric)
- The Prisoner's dilemma (PD) game is a classic game theory scenario where two people could cooperate and yield a positive result but don't thanks to how the pay offs are structured. Two suspects, Blue and Red, are arrested by the police on some mundane crime: theft. The police have sufficient evidence for a conviction but suspect the two are involved in a much larger crime: drug possession. Having separated both prisoners, the police visit each of them to offer the same deal:
- The Prisoner's Dilemma is a classic problem in game theory. It has the paradoxical outcome that members of a group will consciously steer towards a sub-optimal outcome in certain scenarios. The game is usually phrased in terms of two suspects, both of whom have been arrested for a major crime, who are offered a bargain. If both stay silent, each of them can still be convicted of a minor crime and sentenced to 6 months in prison. If one of them confesses, this provides evidence of a major crime. The confessor is rewarded by being let off of all crimes, and the other suspect will serve ten years in prison. If both confess, they will both serve two years in a plea for the major crime.
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| abstract | - The Prisoner's dilemma (PD) game is a classic game theory scenario where two people could cooperate and yield a positive result but don't thanks to how the pay offs are structured. Two suspects, Blue and Red, are arrested by the police on some mundane crime: theft. The police have sufficient evidence for a conviction but suspect the two are involved in a much larger crime: drug possession. Having separated both prisoners, the police visit each of them to offer the same deal:
* If they both confess, each will receive a 10-year sentence.
* If one rats the other out and the other remains silent, the betrayer goes free and the silent accomplice receives the full 15-year sentence. (Ten for the charge, five for lying to the police.)
* If both stay silent, the police can sentence both prisoners to only two years in jail for the minor charge. Each prisoner must make the choice of whether to betray the other or to remain silent. However, neither prisoner knows for sure what choice the other prisoner will make. So the question this dilemma poses is: What will happen? How will the prisoners act?
- The prisoner's dilemma
- The prisoner's dilemma was a theoretical problem used in game theory, which demonstrated how cooperation, or a lack of it, could affect the outcome of a situation. If two prisoners were separated and each was given the opportunity to betray his accomplice, there were several different outcomes depending on what each decided and what his accomplice did. Dr Judson had a logic diagram of the prisoner's dilemma on the blackboard in his office at Maiden's Point. The Seventh Doctor recognised it immediately, which enabled him to break the ice with Judson. (TV: The Curse of Fenric)
- The Prisoner's Dilemma is a classic problem in game theory. It has the paradoxical outcome that members of a group will consciously steer towards a sub-optimal outcome in certain scenarios. The game is usually phrased in terms of two suspects, both of whom have been arrested for a major crime, who are offered a bargain. If both stay silent, each of them can still be convicted of a minor crime and sentenced to 6 months in prison. If one of them confesses, this provides evidence of a major crime. The confessor is rewarded by being let off of all crimes, and the other suspect will serve ten years in prison. If both confess, they will both serve two years in a plea for the major crime. It is obvious that the best outcome (the Pareto optimum) for the group would be if both prisoners cooperated and stayed silent: Six months for both prisoners. However, in the "default" setting of the Prisoner's dilemma, we assume that the prisoners are not given the chance to work out such a strategy and that they are interested in their own wellbeing first. Prisoner A will now analyze his options:
* If Prisoner B chooses "don't confess", Prisoner A's best choice will be "confess": A gets out of prison immediately.
* If Prisoner B chooses "confess", Prisoner A's best choice will be "confess", too: 2 years is better than 10 years. (The case for Prisoner B is symmetric.) Using this reasoning, both prisoners will choose "confess" as providing the best outcome for themselves in all circumstances, even though it is not best result for the group. The strategy "confess" is a strictly dominant strategy: The choice of the Prisoner B does not change the way Prisoner A will act. The "confess/confess" scenario is also the only Nash equilibrium in this problem.
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