There seems to be consensus that the Department of Justice's 1984 Vertical Merger Guidelines do not reflect either modern theoretical and empirical economic analysis or current agency enforcement policy. Yet widely divergent views of preferred enforcement policies have been expressed among...

Economists widely agree that, absent sufficient efficiencies or other offsetting factors, mergers that increase concentration substantially are likely to be anticompetitive. Further, holding everything else equal, the magnitude of anticompetitive effects tends to be larger, the larger is the...

This article addresses the application of the economic literature on merger simulation to the practical context of antitrust enforcement. It highlights the value of simple simulations as a basis for creating screens and presumptions – particularly the gross upward pricing pressure index for...

This article takes a fresh look at a longstanding issue in antitrust economics and policy: the problem of oligopoly coordination. First, it explains why coordinated conduct in oligopoly markets is a serious problem and an appropriate concern of antitrust enforcement. It shows that empirical...