We consider a model featuring a single-product natural monopoly, which faces evaders, i.e., individuals that may not pay the price. By exerting a costly effort, the firm can deter evasion. To maximize the total surplus, a regulator sets the price, the level of deterrence effort, and socially...

Theoretical standard models and regulatory actions often ignore that firms are competing with other firms in related markets. In these contexts, cross-price relationships should be taken into account. The usual instinct with multiproduct firms would be to use Ramsey prices to find optimal...

We develop a model of vertical innovation in which firms incur a market entry cost and choose a unique level of quality. Once established, firms compete for market shares, selling to consumers with heterogeneous tastes for quality. The equilibrium of the pricing game exists and is unique within...