Abstract
Studies of the impact of horizontal mergers on market power typically impose an immediate adjustment of market power following a merger. This paper adopts an alternative procedure to estimate the effect of four mergers on market power in the U.S. steel industry. Namely, by estimating a switching regression model that incorporates profit-maximizing behavior, the results show that mergers generally increased market power in the steel industry. However, it did take some time for market power to fully adjust after each merger.