Equilibrium existence with spillover demand

Abstract

Non-existence of a pure-strategy Nash equilibrium is a persistent problem in oligopoly models where sellers compete in prices and quantities. At the heart of this problem are unserved customers who are still willing to visit a less preferred supplier (i.e., so-called spillover demand). This note develops a consumer behavior model with spillover demand. Within this model there is a class of demand specifications for which a pure-strategy Nash equilibrium exists. This price-quantity equilibrium is shown to coincide with the Bertrand price equilibrium.