Firms often concentrate on a narrow range of activities and claim to forgo other, apparently profitable, opportunities. This pursuit of narrow strategies is applauded by some academics who study strategic management. The authors present two related theoretical models in which firms do indeed...

This paper seeks to explain why monopolies keep their nominal prices constant for longer periods than do tight oligopolies. The authors show that cost changes create a larger incentive for duopolists to change their prices, while demand changes tend to have a greater effect on a monopolist. When...

The authors formulate a complete, but analytically simple, equilibrium model of vertical mergers to evaluate the logic of standard vertical foreclosure claims and the criticisms made of those claims. The model includes incentives of the integrated firm and unintegrated input suppliers to exclude...

This paper studies implicitly colluding oligopolists facing fluctuatingdemand. The credible threat of future punishments provides the discipline that facilitates collusion. However, the authors find that the temptation to unilaterally deviate from the collusive outcome is often greater when...

The authors analyze incomplete long-term contracts when buyers incur relationship-specific set-up costs and sellers choose product or service quality that is not verifiable to third parties. If set-up costs are observable, the first-best outcome can be achieved even though contracts cannot...