We study information transmission between informed experts and an uninformed decision-maker who only takes binary decisions. In the single expert case, we show that information transmission can only be relatively poor. Hence, even sophiscated communication games do not yield equilibria which (ex...

Decisions of national competition authorities have important effects on other jurisdictions. We provide a framework to quantify the domestic and cross-border effects of mergers, and to draw conclusions for the coordination of national merger policies. We develop a two-country model with many...

I review previous approaches to modelling oligopoly in general equilibrium, and propose a new view which in principle overcomes their deficiencies: modelling firms as large in their own market but small in the economy as a whole. Implementing this approach requires a tractable specification of...

Der vorliegende Beitrag wendet die dynamische Wettbewerbstheorie von Wolfgang Kerber und anderen auf aktuelle Fragen der Wettbewerbspolitik an. Damit zeigt der Beitrag, dass dynamische Wettbewerbstheorien sehr wohl zu konkreten wettbewerbspolitischen Empfehlungen führen und einen wichtigen...

Digitale Großkonzerne wie Facebook, Google & Co. stellen die Wettbewerbsinstitutionen vor neue Herausforderungen. Mithilfe der Charakteristiken von Plattformmärkten können sie ihre Macht und Verhandlungsstärke zunehmend verfestigen und darüber hinaus marktübergreifende digitale Ökosysteme...

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...

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 show how temporary ownership by private equity firms affects industry structure, competition and welfare. Temporary ownership leads to strong investment incentives because equilibrium resale prices are determined by buyers incentives to block rivals from obtaining assets. These incentives...

This paper investigates the effects on tacit collusion of increased market transparency on the consumer side of a market in a differentiated Hotelling duopoly. Increasing market transparency increases the benefits to a firm from underbutting the collusive price. It also decreases the punishment...

The paper first summarizes the benefits of competition, i.e. why competitive markets are more efficient than oligopolistic or monopolistic markets, and the threats to competitive markets from cartels, concentration, and government interference. In the main part, the paper presents the key...