On Revising the Horizontal Merger Guidelines

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Luke Froeb, Dec 16, 2009

To determine whether a proposed merger is anticompetitive, one must compare the world without the merger which is observed to the world with the merger, which typically is not. Viewed in this way, the primary problem confronting antitrust enforcers is how to draw inference about the unobserved state of the world. The same problem characterizes monopolization or abuse-of-dominance cases, except that the wor