This is a survey of the economic principles that underlie antitrust law and how those principles relate to competition policy. We address four core subject areas: market power, collusion, mergers between competitors, and monopolization. In each area, we select the most relevant portions of...

Switching costs and network effects bind customers to vendors if products are incompatible, locking customers or even markets in to early choices. Lock-in hinders customers from changing suppliers in response to (predictable or unpredictable) changes in efficiency, and gives vendors lucrative ex...

This article investigates downstream firms' ability to collude in a repeated game of competition between supply chains. We show that downstream firms with buyer power can collude more easily in the output market if they also collude on their input supply contracts. More specifically, an implicit...

We study the effectiveness of firms' compliance programs by conducting a field experiment in which we disclose to a subset of Japanese firms that the firm is potentially engaging in illegal bid-rigging. We find that the information that we disclose affects the bidding behavior of the treated...

When commodity prices rise, wholesalers and retailers of products derived from basic commodities respond by passing along at least a portion of the price increase to consumers. In this paper we examine whether firms respond differently to positive commodity price shocks than to negative...

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...

When is the modeller introducing more error when analysing a Cournot market with private cost information - when ignoring market power or when ignoring the impact of incomplete information? Is the welfare loss at the market outcome driven by private information or by market power? The answer,...