We model competition between two unregulated mobile phone companies with price-elastic demand and less than full market coverage. We also assume that there is a regulated full-coverage fixed network. In order to induce stronger competition, mobile companies could have an incentive to raise their...

We present a model with firms selling (homogeneous) products in two imperfectly segmented markets (a "high-demand" and a "low-demand" market). Buyers are mobile but restricted by transportation costs, so that imperfect arbitrage occurs when prices differ in both markets. We show that equilibria...

We analyze the effects of accidents and liability obligations on the incentives of car manufacturers to monopolize the markets for their spare parts. We show that monopolized markets for spare parts lead to higher overall expenditures for consumers. Furthermore, while the manufacturers invest...

We analyze a vertical structure with an upstream monopoly and two downstream retailers. Demand is uncertain but each retailer receives an informative private signal about the state of the demand. We construct an incentive compatible and ex ante balanced mechanism which induces the retailers to...