Abstract We investigate whether vertical separation reduces quality discrimination and increases welfare. Consider an industry consisting of a vertically integrated firm, the incumbent, and an independent retailer, the entrant, which requires access to the services of the incumbent's wholesaler....

The European Commission believes that for the regulation of next generation fixed telecommunications networks the continuity approach is preferable to the equality of access approach and the no-regulation approach. According to the European Commission, (i) functional separation eliminates...

We analyze if two-part access tariffs solve the dynamic consistency problem of the regulation of next generation networks. We model the industry as a duopoly, where a vertically integrated incumbent and a downstream entrant, that requires access to the incumbent's network, compete on Hotelling's...

The question of whether bundles of telecommunication services are relevant product markets is addressed. As a first step, demand for bundles of services, as well as the associated services, is modeled as a discrete choice problem with a potentially large number of products. A unique invoice...

In this article, one makes two points about the impact of bundles on competition and regulatory policy. First, one argues that the growing importance of bundles requires an adjustment in the current framework of relevant product markets for individual services, and that the traditional tools of...

We analyze the product differentiation decision of a downstream entrant that purchases access to a bottleneck input from one of two vertically integrated incumbents, who will compete with him in the downstream market. First, an entrant chooses his product, then the entrant negotiates the access...

We evaluate the impact on market power and efficiency of a series of mergers on three Portuguese non-life insurance markets. We specify and estimate, with a panel of firm-level data, a structural model which includes: preferences, technology, and a market equilibrium condition. Firms' demand...