Price-Matching Guarantees and Equilibrium Selection in a Homogenous Product Market: An Experimental Study

Price-matching guarantees have been alleged to sustain collusive prices in a homogenous product market. Theories in this literature also suggest that there exist multiple equilibria (i.e., a set of price equilibria between the competitive and the monopoly price) when all sellers adopt these guarantees in such a market. Theoretical prediction in this case fails to pin down the actual behavior of players a priori. This paper illustrates the essential role of controlled experiment in testing the collusive theory of price-matching guarantees and thereby shedding light on the embedded equilibrium selection problem. In particular, this paper studies two highly stylized market models, obtains testable predictions, and lays out the design of the controlled experiment. Results indicate that these guarantees facilitate collusion among sellers and thus solve the equilibrium selection problem considerably. I am grateful to Jim Cox, Martin Dufwenberg, Haimanti Bhattacharya, and the editor of this journal and the two referees for their suggestions. I thank seminar participants at the University of Arizona and North American Economic Science Association meeting at Tucson, 2003 for their helpful comments. A research grant from ESL, University of Arizona, for this project is gratefully acknowledged. I am solely responsible for any remaining errors and omissions.