Asymmetric cross-price effects and collusion

Asymmetries in cross-price elasticities have been demonstrated by several empirical studies, but received little attention by the theoretical literature. In this paper we study from a theoretical stance how introducing asymmetry in the substitution effects influences the sustainability of collusion. We first characterize the equilibrium of a linear Cournot duopoly with substitute goods, and consider substitution effects which are asymmetric in magnitude. Since the two goods are asymmetric strategic substitutes, the production decisions are driven by the firm which is relatively less influenced by the rival. We then study partial collusion using the folk theorem's solution concept. Our main result shows that the interval of quantities supporting collusion in the asymmetric setting is always smaller than the interval in the symmetric benchmark. The asymmetry in the substitution effects thus hinders collusion.