MULTILEVEL EVOLUTION IN POPULATION GAMES

In this paper, we analyze a generalization of the evolutionary model o f Kandori, Mailath, & Rob (1993) where the population is partitioned i nto groups and evolution takes place ''in parallel'' at the following two levels: (i) within groups, at the lower level; among groups, at th e higher one. Unlike in their context, efficiency considerations alway s overcome those of risk-dominance in the process of selecting the lon g-run equilibrium. This provides an explicitly dynamic basis for a con clusion reminiscent of those put forward in the biological literature by the so-called theories group selection. From a normative viewpoint, it suggests the potential importance of ''decentralization'', here un derstood as local and independent interaction.