We start the survey by reviewing the implications of horizontal and vertical product differentiation on market structure under the assumption of single-product firms. Then, we analyze the main results of the multi-product firm models, both when variants are assumed differentiated in vertical...

A theory of the firm based on strategic decision-making highlights governance as a central issue. Preferences vary over strategy but not all interests are currently being represented, resulting in a failure to govern in the public interest. As solutions, we consider the design of company law and...

I discuss the use of simulation techniques to evaluate unilateral effects of horizontal mergers and the pitfalls that one can encounter when using them. Simple econometric models are desirable because they can be implemented in a short period of time and can be understood by non experts....

We examine the development of UK outlets of a major fast food chain, from inauguration in 1974 until 1990, after which industry structure changed somewhat. The chain effectively introduced the counter-service burger concept. Locational spread across local authority district markets is explained...

We study the effects of market structure on entry using data from the UK fast food (counter-service burger)industry over the years 1991-1995. Over this period, the market can be characterized as a duopoly. We find that market structure matters greatly: for both firms, rival presence increases...

Chain-stores now dominate most areas of retailing. While retailers may operate nationally or even internationally, the markets they compete in are largely local. How should they best operate pricing policy in respect of the different markets served - price uniformly across the local markets or...

A mechanism implements a social choice correspondence f in mixed Nash equilibrium if at any preference profile, the set of all pure and mixed Nash equilibrium outcomes coincides with the set of f-optimal alternatives at that preference profile. This definition generalizes Maskin’s definition...

For each set of candidates at state and each profile of voters' preferences over running candidates a voting corresponsence selects a set of candidates. following Dutta, Jackson and Le Breton (Econometrica 2001) a voting correspondence is candidate stable if a candidate never benefits from...

This chapter gives a flavour of recent theoretical work on coalition formation and political parties. I survey recent work on both pre-election coalition formation and post election coalition (or government) formation. A number of alternative rationales for the formation of parties are compared...

We extend the analysis of Dutta, Jackson and Le Breton (Econometrica 2001) on strategic candidacy to probabilistic environments. For each configuration of the agenda and each profile of voters' preferences over running candidates a probabilistic voting procudure selects a lottery on the set of...