数理人口学・数理生物学セミナー

過去の記録 ~03/28次回の予定今後の予定 03/29~


2006年09月27日(水)

16:30-17:30   数理科学研究科棟(駒場) 123号室
中丸麻由子 氏 (東京工業大学)
The coevolution of altruism and punishment:role of the selfish punisher
[ 講演概要 ]
Punishment is an important mechanism promoting the evolution of altruism among nonrelatives. We investigate the coevolution of altruism and punitive behavior, considering four strategies: a cooperator who punishes defectors (AP), a pure cooperator (AN), a defector who punishes defectors (selfish punisher or SP), and a pure defector (SN). We especially focus on the effects of SP on the coevolution of altruism and punishment, studying both the score-dependent viability model (whereby the game's score affects survivorship only) and the score-dependent fertility model (whereby the score affects fertility only). In the viability model of a completely mixed population, SP helps cooperators to evolve, but SP does not in the fertility model. In both models of a lattice-structured population, SP promotes the spread of AP, but AN discourages it. These results indicate that punishment is a form of spite behavior and that different models give different magnitude of advantage to spite behavior.