robin

Web, Science, Politique

  • Iterated Prisoner’s Dilemma contains strategies that dominate any evolutionary opponent
    http://www.pnas.org/content/109/26/10409.full?sid=170efdfd-ac48-4ea2-9851-064e11184b81

    The two-player Iterated Prisoner’s Dilemma game is a model for both sentient and evolutionary behaviors, especially including the emergence of cooperation. It is generally assumed that there exists no simple ultimatum strategy whereby one player can enforce a unilateral claim to an unfair share of rewards. Here, we show that such strategies unexpectedly do exist. In particular, a player X who is witting of these strategies can (i) deterministically set her opponent Y’s score, independently of his strategy or response, or (ii) enforce an extortionate linear relation between her and his scores. Against such a player, an evolutionary player’s best response is to accede to the extortion. Only a player with a theory of mind about his opponent can do better, in which case Iterated Prisoner’s Dilemma is an Ultimatum Game.

    • It is worth contemplating that, though an evolutionary player Y is so easily beaten within the confines of the IPD game, it is exactly evolution, on the hugely larger canvas of DNA-based life, that ultimately has produced X, the player with the mind.

      Freeman Dyson ?!

      (Le darwinisme et le dilemme du prisonnier, c’était mon sujet de thèse…)

      #théorie_des_jeux #évolution #coopération #intelligence #darwinisme

    • Oui, c’est en lisant un article sur Dyson dans Quanta que je suis tombé sur ce papier. Je n’ai pas encore eu le temps de creuser, mais ça m’a paru pas mal :)

      Ta thèse est dispo ?

    • sur microfilm ! je crois même pas en avoir conservé ni les sources ni le PDF… c’était juste 5 ans de travail, c’est pas grave :)

    • ça fait plaisir mine de rien qu’un vieux comme Dyson s’intéresse encore (et publie !) des bons papiers de recherche, à 88 ans…

    • Tu me confortes dans mon opinion que les études ne servent à rien ;) Mais c’est dommage, j’aurais bien jeté un œil dessus quand même.

      Il se trouve justement que Dyson causait de son opposition au système des thèses doctorales :

      https://www.simonsfoundation.org/quanta/20140326-a-rebel-without-a-ph-d

      I’m very proud of not having a Ph.D. I think the Ph.D. system is an abomination. It was invented as a system for educating German professors in the 19th century, and it works well under those conditions.

      Il a l’air plutôt frais, c’est le moins qu’on puisse dire.