Traditional game theory studies strategic interactions in which the agents make rational decisions. Evolutionary game theory differs in two key respects: the focus is on large populations of individuals who interact at random rather than on small numbers of players; and individuals are assumed...

Social norms are customary or ideal forms of behavior to which individuals in a group try to conform. From an analytical standpoint, the key feature of social norms is that they induce a positive feedback loop between individual and group behavior: the more widely that a norm is practiced by...