The behaviour of urban populations is compared with the systems directing behaviour in individuals. This is both a metaphor and a mechanistic parallel. The biological model draws upon recent developments in brain research and psychological and cultural anthropology. The development and operation...

We develop a model in which competition in the labor market may produce worker-firm matches that are inferior to those obtained in the absence of competition. This result contrasts with the conventional wisdom that competition among employers allocates scarce talent efficiently. In a model in...