The price of anarchy when costs are non-separable and asymmetric

Abstract

In this paper we characterize the "price of anarchy", i.e., the inefficiency between user and system optimal solutions, when costs are non-separable, asymmetric and nonlinear, generalizing earlier work that has addressed "the price of anarchy" under separable costs. This generalization models traffic equilibria, competitive multi-period pricing and competitive supply chains. The bounds established in this paper are tight and explicitly account for the degree of asymmetry and nonlinearity of the cost function. We introduce an alternate proof method for providing bounds that uses ideas from semidefinite optimization. Finally, in the context of multi-period pricing our analysis establishes that user and system optimal solutions coincide. © Springer-Verlag Berlin Heidelberg 2004.