On the Existence of Cournot-Nash Equilibrium in Symmetric n-Firm Oligopoly - A detailed Proof by Tarski’s Fixed Point Theorem
نویسنده
چکیده
Existence of symmetric n-firm Cournot Nash equilibrium has been proven by [4] McManus (1964) and [7] Roberts/Sonnenschein (1976), later ones do not require concave profit functions. [14] Vives (1990), pp. 317 suggested a connection to Tarski’s fixed point theorem and sketched a proof in the framework of lattice theory and the theory of supermodular games. Further sketches of the proof can be found in [1] Amir (1996), p. 146 and [13] Vives (2000), pp. 95, but no detailed proof is provided. In this note I write down the detailed proof. JEL-Classifications: C72.
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تاریخ انتشار 2002