Title: Competition and efficiency in congested markets
Description: "We study the efficiency of oligopoly equilibria in congested markets.  The motivating examples are the allocation of network flows in a communication network or of traffic in a transportation network.  We show that increasing competition among oligopolists can reduce efficiency, measured as the difference between users' willingness to pay and delay costs.  We characterize a tight bound of 5/6 on efficiency in pure strategy equilibria.  This bound is tight even when the number of routes and oligopolists is arbitrarily large.  We also study the efficiency properties of mixed strategy equilibria"--National Bureau of Economic Research web site.
Subjects: Competition, Mathematical models, Oligopolies