Economic analysis of competition regulation is most developed in the domain of horizontal mergers, and modern agency guidelines reflect a substantial consensus on the appropriate template for merger assessment. Nevertheless, official protocols are understood to rest on a problematic market...

We analize a market in the process of liberalization. Consumers are biased in favor of the incumbent firm and we assume that they can discover the true value of new suppliers only by switching. In an infinitely-repeated game setting with Bertrand competition, we first show that efficient entry...

This article studies the design of optimal mechanisms to regulate entry in natural oligopoly markets, assuming the regulator is unable to control the behavior of firms once they are in the market. We adapt the Clarke-Groves mechanism, characterize the optimal mechanism that maximizes the...

We consider market dynamics in a reduced form model. In the simplest version, there are two investors and several small noninvesting firms. In each period, one investor can acquire a small firm, the other investor decides about market entry. After that all firms play an oligopoly game. We derive...

We customize the aggregative game approach to oligopoly to study asymmetric media markets. Advertiser, platform, and consumer surplus are tied together by a simple summary statistic. When media are ad-financed and ads are a nuisance to consumers we establish see-saws between consumers and...

We provide an extensive and general investigation of the effects on industry performance (profits and social welfare) of exogenously changing the number of firms in a Cournot framework. This amounts to an in-depth exploration of the well-known trade-off between competition and production...

We consider a software vendor selling both a monopoly platform (e.g. operating system) and an application that runs on this platform. He may face competition by an entrant in the applications market. Consumers are heterogeneous in their preferences for both the platform and the applications....

We consider a software vendor first selling a monopoly platform and then an application running on this platform. He may face competition by an entrant in the applications market. The platform monopolist can benefit from competition for three reasons. First, his profits from the platform...

We use cumulative reaction functions to compare long-run market structures in aggregative oligopoly games. We first compile an IO toolkit for aggregative games. We show strong neutrality properties across market structures. The aggregator stays the same, despite changes in the number of firms...

Voice over Internet Protocol (VoIP) such as Skype that enables users to make free internet-based calls to other users has been seen as a threat to voice revenues by traditional network operators. While some mobile network operators (MNOs) attempt to block Skype's entry on their networks, some...