Competition, efficiency and collective behavior in the "El Farol" bar model

The El Farol bar model, proposed to study the dynamics of competition of ag ents in a variety of contexts (W.B. Arthur, Amer. Econ. Assoc. Fap. Proc. 8 4, 408 (1994)) is studied. We characterize in detail the three regions of t he phase diagram (efficient, better than random and inefficient) of the sim plest version of the model (D. Challet! Y.-C. Zhang, Physica A 246, 407 (19 97)). The efficient region is shown to have a rich structure, which is inve stigated in some detail. Changes in the payoff function enhance further the tendency of the model towards a wasteful distribution of resources.