Isamu Okada and Hitoshi Yamamoto
We analysed an adaptive process of conditionally risk behaviour by using an agent-based simulation. We observed that relative high-risk behaviours easily survive in a tournament game. Further, the more high-risk behaviours, but not the highest ones, are most adaptive in a society in which mutants always can invade. These insights not only correspond to human behaviour described by the prospect theory, but also make it possible to explain a rational mechanism which cannot be explained by this theory. While this paper may not be representational, it can provides signicant insights beyond behavioural economics to areas as diverse as evolution theory, social psychology, and consumer behavioural theory. Moreover, we propose some ideas that can be used to extend the model to analyse it circumstantially.