This paper studies horizontal mergers in vertically related markets. In a two-level Cournot model, with an intermediate and a final market, we show that downstream mergers inducing size effects are, ceteris paribus, more profitable than upstream ones. Moreover, a merger at one level reduces the...

This article attempts to determine the optimal antitrust policy against price-fixing when competition authorities imperfectly observe firms' behaviour. By investigating or auditing on markets, authorities can detect collusion. We show that the strenght of investigations depends on the...

This paper generalizes the work of Rothschild and Stiglitz [1976], and is dealing with a game where two principals compete for an agent, when the agent has private information. The studied game has an efficient equilibrium, when the payoff of the principal does not depend on private information....

This paper considers a competitive insurance market under moral hazard and adverse selection, in which preventive efforts and self-protection costs are unobservable by insurance companies. Under reasonable assumptions, the conclusions of Rothschild and Stiglitz (1976) are preserved in our...