๐ค AI Summary
This paper investigates the convergence of best-response dynamics in a multi-firm Cournot oligopoly under heterogeneous marginal costs. Considering linear demand and asymmetric costs, we employ fixed-point theory, linear system stability analysis, and combinatorial enumeration to rigorously establish that the long-run behavior of the system can only converge either to the unique Nash equilibrium or to a two-cycle oscillationโno higher-period cycles or chaos are possible. We provide the first necessary and sufficient conditions for the existence of two-cycle oscillations, along with a complete classification thereof, and design an *O*(*n*)-time linear algorithm to efficiently enumerate all such oscillatory solutions. By relaxing the conventional assumption of homogeneous costs, our work reveals how cost heterogeneity structurally constrains dynamic complexity. The results establish a new theoretical benchmark and computational toolkit for modeling oligopolistic dynamics.
๐ Abstract
In this paper, we consider the dynamic oscillation in the Cournot oligopoly model, which involves multiple firms producing homogeneous products. To explore the oscillation under the updates of best response strategies, we focus on the linear price functions. In this setting, we establish the existence of oscillations. In particular, we show that for the scenario of different costs among firms, the best response converges to either a unique equilibrium or a two-period oscillation. We further characterize the oscillations and propose linear-time algorithms for finding all types of two-period oscillations. To the best of our knowledge, our work is the first step toward fully analyzing the periodic oscillation in the Cournot oligopoly model.