WARDROP EQUILIBRIA —TO BE PUBLISHED IN “ENCYCLOPEDIA OF OPERATIONS RESEARCH AND MANAGEMENT SCIENCE. EDITED BY J. J. COCHRAN. WILEY”—

Wardrop equilibria are commonly used as a solution concept of network games when modeling transportation and telecommunication networks with congestion. This concept assumes that players select a route that minimizes the time or cost incurred in its traversal. This behavioral assumption admits convenient mathematical descriptions, and efficient algorithms for the computation of equilibria are available. For that reason, planners have been making use of this concept for decades for evaluating projects, optimizing tolls, estimating demands, and a myriad of applications arising from extensions of the basic model. In this article, we introduce the basic model, explain strategies for computation of equilibria, and discuss the extent of the inefficiency arising from the self-minded behavior of the players. In addition, we provide some generalizations of the basic model.

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