We study optimal merger policy in a dynamic model in which the presence of scale economies implies that firms can reduce costs through either internal investment in building capital or through mergers. The model, which we solve computationally, allows firms to invest or propose mergers according...

Concentration-based screens for horizontal mergers, such as those employed in the US DOJ and FTC Horizontal Merger Guidelines, play a central role in merger analysis. However, the basis for these screens, in both form and level, remains unclear. We show that there is both a theoretical and an...

Health care report cards - public disclosure of patient health outcomes at the level of the individual physician and/or hospital - may address important informational asymmetries in markets for health care, but they may also give doctors and hospitals incentives to decline to treat more...

This chapter presents an overview of advances in the structural analysis of contracting in vertical markets over the past fifteen years. We provide a discussion of theoretical models of contracting and bargaining that form the basis of recent empirical work, and then present common approaches...

We study targeted lockdowns in a multi-group SIR model where infection, hospitalization and fatality rates vary between groups--in particular between the "young", "the middle-aged" and the "old". Our model enables a tractable quantitative analysis of optimal policy. For baseline parameter values...

We analyze the optimal dynamic policy of an antitrust authority towards horizontal mergers when merger proposals are endogenous and occur over time. Approving a currently proposed merger will affect the profitability and welfare effects of potential future mergers, the characteristics of which...

Tied sales have a long history of scrutiny under the antitrust laws of the United States. The primary basis for the condemnation of this practice has been the court's belief in what has come to be known as the "leverage theory" of tying: that is, that tying provides a mechanism whereby a firm...

Elzinga/Hogarty inflow/outflow analysis is a mainstay of geographic market definition in antitrust analysis. For example, U.S. antitrust agencies lost several hospital merger challenges when evidence showed that a nontrivial fraction of local patients traveled outside the local community for...

We study the effects of antitrust policy in industries with continual innovation. A more protective antitrust policy may have conflicting effects on innovation incentives, raising the profits of new entrants, but lowering those of continuing incumbents. We show that the direction of the net...

The purpose of this paper is to present estimates of production functions for hospitals in which a measure of the level of physician input is utilized. Since no data on the total number of hours worked by non-salaried physicians is available for a large sample of U.S. hospitals, alternative...