It's your turn: experiments with three-player public good games

We report results from experiments designed to investigate the prevalence of turn-taking in three-person finitely repeated threshold public good games without communication. Individuals can each make a discrete contribution. If the number of contributors is at least equal to the threshold, a public benefit accrues to all group members. Players take turns to provide the public good each round when the endowments are homogeneous. When the turn-taking path is at odds with efficiency or under private information of endowments, players seldom engage in taking turns. An endogenous-move protocol limits the frequency of mis-coordinated outcomes every round

Allocation distribuée de ressources dans les réseaux virtuels privés

Un réseau virtuel privé (VPN) est défini comme un réseau logique qui permet de connecter plusieurs utilisateurs qui appartiennent au même groupe d’utilisateurs (entreprise, fournisseurs, etc.) et disperser géographiquement. Un VPN est protégé par un contrat d’accord de service (SLA) entre le client et le fournisseur de service (ISP) qui définit les différents paramètres tels que le niveau de service (disponibilité et performance) et la qualité de service (QoS). À travers un modèle non-coopératif répétitif, nous proposons une architecture autonome et distribuée pour des fins d’allocation des ressources au sein d’un VPN en permettant les opérateurs VPN de bien gérer leur bande passante d’une façon optimale et de partager leurs ressources non utilisables (bande passante), en assurant la qualité de service sans l’intervention de l’ISP. Pour inciter les opérateurs VPN à collaborer dans ce modèle, nous avons adopté la théorie de jeux comme un mécanisme et plus spécifiquement le modèle non coopératif répété de la théorie de jeux. Ce modèle offre aux opérateurs la possibilité de gérer d’une façon autonome leur bande passante, permet aux VPN(s) d’atteindre la qualité de service souhaitée, et ainsi assurer la disponibilité des ressources à court, moyen et long terme

Cooperation and coordination in the turn-taking dilemma

In many real-world situations, "cooperation " in the simple sense of the Prisoner's Dilemma is not sufficient for success: instead, cooperators must precisely coordinate more complex behaviors in a noisy environment. We investigate one such model, the Turn-Taking Dilemma, a variant of the repeated Pris-oner's Dilemma in which the highest total payoff is achieved not by simultaneous mutual cooperation, but by taking turns defecting (alternating temptation and sucker payoffs). The Turn-Taking Dilemma more accurately models i:ateractions where players must take short-term losses for long-term gains: situations marked by the intricate give-and-take of bargaining and compromise. Using "evolutionary dominance " as a general measure of performance, we investigated which strategies are most successful in Turn-Taking Dilemma interactions. Our experiments demonstrate that turn-taking can be achieved in a noisy envi-ronment, even when agents have strict resource constraints (limited memory strategies). Top strategies such as EXALT2 can effectively coordinate turn-taking undeer noise, while exploiting cooperators and resisting exploitatiou by defectors; these strategies are likely to achieve succc ~ in the variety of real-world interactions modeled by the Turn-Taking Dilemma. 1 Two models of cooperation The Prisoner's Dilemma, in its various forms, is widely used to model the evolution of cooperation in interactions between individuals with partially conflicting goals. In particular, two variants of the problem have captured the attention of the research community. In the Iterated Prisoner's Dilemma (IPD), players simultaneously choose between cooperation for mutual benefit and defection for individual benefit, and this decision situation is repeated over a number of rounds (Axelrod and Hamilton, 1981). In the Alternating Prisoner's Dilemma (APD), players alternate turns, and on each player's turn he must choose whether to cooperate or defect (Nowak and Sigmund, 1994; Frean, 1994). For both of these models, the potential outcomes are given in the following payoff table