This paper introduces the Werden-Froeb Index (WFI) to assist in evaluating merger-specific efficiencies in horizontal mergers. The index measures the weighted average reduction in marginal costs required to restore pre-merger equilibrium prices and quantities after the (full or partial) merger...

This discussion paper resulted in an article in the 'Journal of Law Economics & Organization' (2013). Volume 29(5), pages 1114-1144.<P> We estimate the deterrence effects of U.S. merger policy instruments with respect tothe composition and frequency of future merger notifications. Data from the...</p>

We formulate a simple model of optimal defensive disclosure by a monopolist facinguncertain antitrust enforcement and test its implications using unique data on defensivedisclosures and patents by IBM during 1955-1989. Our results indicate that strongerantitrust enforcement leads to more...

An important question in the dynamic European wholesale markets for electricity is whether to define the geographical market at the level of an individual member state or more broadly. We show that if we currently take the traditional approach by considering for each member state whether there...

In a circular city model, I consider network design and pricing decisions for asingle fast transport connection that faces competition from a slower but betteraccessible transport mode. To access the fast transport network individuals haveto make complementary trips by slow mode. This fact has...

We develop a method to screen for local cartels. We first test whether there is statistical evidence of clustering of outlets that score high on some characteristic that is consistent with collusive behavior. If so, we determine in a second step the most suspicious regions where further...

We study mergers in a market where N firms sell a homogeneous good and consumers search sequentially to discover prices. The main motivation for such an analysis is that mergers generally affect market prices and thereby, in a search environment, the search behavior of consumers. Endogenous...

This paper studies the incentives to merge in a Bertrand competition model where firms sell differentiatedproducts and consumers search for satisfactory deals. In the pre-merger symmetricequilibrium, the probability that a firm is the next one to be visited by a consumer is equal acrossfirms not...

This paper is the first to examine the effect of minimum price guaranteesin a sequential search model. Minimum price guarantees are notadvertised and only known to consumers when they come to the shop.We show that in such an environment, minimum price guarantees increasethe value of buying the...

See also the article <I>Search Costs, Demand-side Economies, and the Incentives to merge under Bertrand Competition</I> in the 'Rand Journal of Economics'(2013). Volume 44, issue 3, pages 391-424.<P> This paper studies the incentives to merge in a Bertrand competitionmodel where firms sell differentiated...</p></i>