The externalities advertisers receive from newspaper readers and that operating system users receive from software developers are among the leading features of those “platform” industries. However, they are rarely incorporated into applied models of imperfect competition. We argue this...

I study how firms actually compete in nonlinear tariffs by analyzing whether the incumbent and entrant’s decisions to offer a given number of tariff options are interrelated. The goal is to shed some light on those dynamic and strategic aspects of tariff menus that are currently ignored by...

Local telecommunications competition was an important goal of the 1996 Telecommunications Act. We evaluate the consumer welfare effects of entry into residential local telephone service in New York State using household-level data from September 1999 to March 2003. We address the prevalence of...

We discuss the case of a monopolist of a base good in the presence of a complementary good provided either by it or by another firm. We assess and calibrate the extent of the influence on the profits from the base good that is created by the existence of the complementary good, i.e., the extent...

In this paper, we evaluate the consumer welfare effects of entry into residential local phone service in New York State. Residential local phone service competition was an important goal of the 1996 Telecommunications Act. We provide a detailed evaluation of its effects on consumer welfare using...

This paper analyzes the impact on consumer prices of the size and biases of price comparison search engines. We develop several theoretical predictions, in the context of a model related to Burdett and Judd (1983) and Varian (1980), and test them experimentally. The data supports the model’s...

We discuss the case of a monopolist of a base good in the presence of complementary goods provided either by it or by other firms. We assess and calibrate the extent of the influence on the profits from the base good that is created by the existence of complementary goods, i.e., the extent of...

This paper discusses the economics of the Internet backbone. I discuss competition on the Internet backbone as well as relevant competition policy issues. In particular, I show how public protocols, ease of entry, very fast network expansion, connections by the same Internet Service Provider...

We discuss the case of a monopolist of a base good in the presence of a complementary good provided either by it or by another firm. We assess and calibrate the extent of the influence on the profits from the base good that is created by the existence of the complementary good, i.e., the extent...

In Cournot's model of complements, the producers of A and B are both monopolists. This paper extends Cournot's model to allow for competition between complements on one side of the market. Consider two complements, A and B, where the A+B bundle is valuable only when purchased together. Good A is...