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

The El Farol bar model, proposed to study the dynamics of competition of agenis in a variety of contexts (W.B. Arthur. Amer. Econ. Assoc. Pap. Proc. 84, 406 (1994)) is studied. We characterize in detail the three regions of the phase diagram (efficient, better than random and inefficient) of the simplest version of the model (D. Challet; Y.-C. Zhang, Physica A 246. 407 (1997)). The efficient region is shown to have a rich structure, which is investigated in some detail. Changes in the payoff function enhance further the tendency of the model towards a wasteful distribution of resources.