Authors:
Akihiro Takahara
1
and
Tomoko Sakiyama
2
Affiliations:
1
Information Systems Science, Graduate School of Science and Engineering, Soka University, Hachioji, Japan
;
2
Department of Information Systems Science, Soka University, Hachioji, Japan
Keyword(s):
Spatila Prisoner’s Dilemma, Memory, System-Size Analysis.
Abstract:
In classical game theory, because players having Defector (D) strategy tend to survive, many studies have been conducted to determine the survival of players with Cooperator (C) strategy. Recently, we have tackled the problem of the evolution of cooperators by proposing a new model called the twisted prisoner’s dilemma (TPD) model. In the proposed model, each player is given a memory length. In situations where neighbors had the same strategy as a player and a higher score than that of the player, the player updated their strategy by ignoring the classical SPD update rule. This new strategy was difficult to choose before the update. Consequently, cooperators could survive even if their memory length was small. In this study, by focusing on the system sizes, performance of the TPD model was determined. Similar results were obtained for various system sizes, except when the system size was extremely small.