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...

This paper shows that generators exercised increasing market power in the England and Wales wholesale electricity market in the second half of the 1990s despite declining market concentration. It examines whether this was consistent with static, non-cooperative oligopoly models, which are widely...

This paper revisits the relationship between transparency on the consumer side and product variety as analyzed in Schultz (2009). We identify two welfare effects of transparency. More transparency decreases price-cost margins which is beneficial forwelfare. On the other hand, more transparency...

Recent court rulings, e.g., in the Gencor and Airtours cases, seem to indicate that the legal concept of joint dominance in oligopolistic markets is equivalent to the economic concept of collusion. This paper argues that the enlargement of the dominance concept to also include oligopolistic...

This paper analyzes the effects of mergers and acquisitions on the markups of non-merging rival firms across a broad set of industries. We exploit expert market definitions from the European Commission's merger decisions to identify relevant competitors in narrowly defined product markets....

This paper revisits the relationship between transparency on the consumer side and product variety as analyzed in Schultz (2009). We identify two welfare effects of transparency. More transparency decreases price-cost margins which is beneficial forwelfare. On the other hand, more transparency...

While often times the Hypothetical Monopolist Test (HMT) utilized in relevant market delineation is implemented with uniform price increases throughout all the goods in the candidate relevant market, since 1984 the versions of the U.S. Merger Guidelines have emphasized that these small but...

We describe a simple initial indicator of whether a proposed merger between rivals in a differentiated product industry is likely to raise prices through unilateral effects. Our diagnostic calibrates upward pricing pressure (UPP) resulting from the merger, based on the price/cost margins of the...

This paper evaluates the recent literature claiming that the US economy has generally become less competitive causing the US economy to perform poorly and that lax antitrust policy is one important reason for the decline in economic performance. Although there certainly are empirical facts...

The prevalence of third-party tracking in our modern ecosystem cannot be ignored. Trackers, on our websites and apps, enable multi-sourced data gathering, at distinct volume, velocity, verity and veracity. While employed by numerous operators, the majority of these trackers are controlled by a...