Many industries are made of a few big firms, which are able to manipulate the market outcome, and of a host of small businesses, each of which has a negligible impact on the market. We provide a general equilibrium framework that encapsulates both market structures. Due to the higher toughness...

We analyze a model of a vertically differentiated duopoly with two regions. These two locations differ for the market size or for the distribution of the willingness to pay for quality of their consumers. Firms sequentially choose to settle in one region and then simultaneously compete in...

This paper analyses successive markets where the intra-market linkage depends on the technology used to produce the final output. We investigate entry of new firms, when entry obtains by expanding the economy, as well as collusive agreements between firms. We highlight the differentiated effects...

We develop a model of strategic networks in order to analyze how trade unions will affect the stability and efficiency of R&D collaboration networks in an oligopolistic industry with three firms. Whenever firms settle wages, the complete network is always pairwise stable and the partially...

In a game with positive externalities, such as e.g. the standard environmental externality game used in the analysis of international environmental agreements, the solutions having the property of coalitional internal stability, when they exist, are compared in this paper with the solutions with...