We compare simultaneous versus sequential moves in R&D decisions within an asymmetric R&D/Cournot model with linear demand (for differentiated products), general R&D costs, and spillovers. Simultaneous play and sequential play (with and without a specified leader) can emerge as appropriate...

With one-way spillovers, the standard symmetric two-period R&D model leads to an asymmetric equilibrium only, with endogenous innovator and imitator. We show how R&D decisions and measures of firm heterogeneity - market shares, R&D shares, and profits - depend on spillovers and on R&D costs....

In the framework of symmetric Cournot oligopoly, this paper provides two minimal sets of assumptions on the demand and cost functions that imply respectively that, as the number of firms increases, the minimal and maximal equilibria lead to (i) decreasing industry price and increasing or...

This note relates to Topkis (1995). We establish via counterexample that:(i) A new monotone transformation of the firms' profit functions may lead to cardinal complementarity when the standard log and identity transformations both fail, and (ii) Topkis's notion of critical sufficient condition...

A two period R&D symmetric Cournot duopoly game with linear demand and costs is analysed under linear (or more general) returns to scale in process R&D. Subgame-perfect equilibrium may call for one firm to fully innovate while the other firm remains just as before. The outcome is a polar duopoly...

We consider a two-period duopoly characterized by a one-way spillover structure in process R&D and a very broad specification of product market competition. We show that a priori identical firms always engage in different levels of R&D, at equilibrium, thus giving rise to an innovator/imitator...

This paper deals with a general version of a two-stage model of R&D and product market competition. We provide a thorough generalization of previous results on the comparative performance of noncooperative and cooperative R&D, dispensing in particular with ex-post symmetry and linear demand...

An infinite-horizon, stochastic model of entry and exit with sunk costs and imperfect competition is constructed. Simple examples provide insights into: (1) the relationship between sunk costs and industry concentration, (2) entry when current profits are negative, and (3) the relationship...

We provide an extensive comparison of the R&D models of d'Aspremont-Jacquemin (1988) and Kamien-Muller-Zang (1992), exposing full or partial conflict in key conclusions and policy prescriptions. Using three separate formal and/or intuitive criteria, we argue that the first model is invalid for...

We consider the issues of endogenous timing and first versus second-mover advantage in differentiated-product Bertrand duopoly with asymmetric linear costs. First, we provide a thorough set of results in the cases where prices are either strategic substitutes and/or complements, dispensing with...