A nonparametric analysis of multi-product oligopolies

We develop revealed preference tests for models of multi-product oligopoly, building on the work in Carvajal et al. (Econometrica 81(6):2351–2379, 2013). We analyze a Cournot model with multiple goods and show that it has testable restrictions when at least one good is produced by two or more firms. We also develop a revealed preference test for Bertrand oligopoly in a setting where each firm produces a single differentiated good, and these goods are potentially substitutes for each other. Our tests require qualitative assumptions on the shape of the demand curves and (in the Bertrand case) their evolution across observations, but they do not rely on the estimation of market demand.