We examine two reasons why a monopoly supplier of software may introduce more upgrades than is socially optimal when the upgrade is backward but not forward compatible, so users who upgrade reduce others' network benefits. One explanation involves a commitment problem: profits and social welfare...

This article reexamines the experience of the Joint Executive Committee, an 1880s railroad cartel, to assess the applicability of the Green and Porter (1984) and Rotemberg and Saloner (1986) theories of price wars. After discussing necessary modifications to the theories, I estimate a number of...

This article studies several attributes of a firm's long-run decisions about organizational structure, attributes that affect the firm's short-run innovative activity. We focus on flexibility, which lowers the future costs of implementing innovations, and research capabilities, which improve the...

We analyze the productivity of information technology in emergency response systems. ``Enhanced 911" (E911) is information technology that links caller identification to a location database and so speeds up emergency response. We assess the impact of E911 on health outcomes using Pennsylvania...

We analyze collusion in an infinitely repeated Bertrand game, where prices are publicly observed and each firm receives a privately observed, i.i.d. cost shock in each period. Productive efficiency is possible only if high-cost firms relinquish market share. In the most profitable collusive...

We analyze a model of oligopolistic competition with ongoing investment. Special cases include incremental investment, patent races, learning by doing, and network externalities. We investigate circumstances under which a firm with low costs or high quality will extend its initial lead through...