The Influence of External Forces on a Monopolistic Market:a statistical physics perspective

Abstract

In this thesis, we consider a discrete choice model with a single homogeneous product and a single seller (the monopoly case) in which a population of individuals with idiosyncratic willingness to pay must choose repeatedly to buy or not a unit of this single homogeneous good at a price determined by the monopolist. Utilities of buyers have positive externalities due to social interactions among customers. If the latter are strong enough, the system has multiple Nash equilibria revealing coordination problems. We assume that individuals learn to make their decisions repeatedly, and study the performances, along the learning path as well as at the reached equilibria, for different learning schemes based on past earned and/or forgone payoffs. We also calculate the monopolist’s profit cumulated during the customers learning process. We discuss analogies between simulated market mechanisms and classical phenomena, in the physics of disordered systems such as phase transition, avalanches, mean-field approximation, quenched and annealed disorder.