2026-03-08T07:25:35Z https://ir.soken.ac.jp/oai

oai:ir.soken.ac.jp:00003662 2023-06-20T14:31:39Z 1:279

Global analyses of evolutionary dynamics and exhaustive search for social norms that maintain cooperation by reputation Global analyses of evolutionary dynamics and exhaustive search for social norms that maintain cooperation by reputation 大槻, 久 OHTSUKI, Hisashi IWASA, Yoh metadata only access © 2006 Elsevier Ltd. Reputation formation is a key to understanding indirect reciprocity. In particular, the way to assign reputation to each individual, namely a norm that describes who is good and who is bad, greatly affects the possibility of sustained cooperation in the population. Previously, we have exhaustively studied reputation dynamics that are able to maintain a high level of cooperation at the ESS. However, this analysis examined the stability of monomorphic population and did not investigate polymorphic population where several strategies coexist. Here, we study the evolutionary dynamics of multiple behavioral strategies by replicator dynamics. We exhaustively study all 16 possible norms under which the reputation of a player in the next round is determined by the action of the self and the reputation of the opponent. For each norm, we explore evolutionary dynamics of three strategies: unconditional cooperators, unconditional defectors, and conditional cooperators. We find that only three norms, simple-standing, Kandori, and shunning, can make conditional cooperation evolutionarily stable, hence, realize sustained cooperation. The other 13 norms, including scoring, ultimately lead to the invasion by defectors. Also, we study the model in which private reputation errors exist to a small extent. In this case, we find the stable coexistence of unconditional and conditional cooperators under the three norms. Elsevier 2007-02-07 eng journal article https://ir.soken.ac.jp/records/3662 http://doi.org/10.1016/j.jtbi.2006.08.018 10.1016/j.jtbi.2006.08.018 00225193 Journal of Theoretical Biology Journal of Theoretical Biology 244 3 518 531