For Bertrand duopoly with linear costs, we establish via a single counterexample that: (i) A new monotone transformation of the firms’ profit functions may lead to the supermodularity of transformed profits when the standard log and identity transformations both fail, and (ii) Topkis’s notion of critical sufficient condition for monotonicity of a Bertrand firm’s best-reply correspondence cannot...

This paper presents a procedure for studying industrial performance and related issues such as changes in the wage structure. This procedure combines cluster analysis and discriminant analysis as a package, and applies this package to time series data. This enables us to organize industrial data into groups with similar wage or performance histories and then to extract summary time-series showi...

We investigate the issue of strategic substitutability/complementarity in differential games. We prove that instantaneous best replies exist if Hamiltonian functions are multiplicative in the control variables. Otherwise, if the Hamiltonians are addively separable w.r.t. controls, a dominant strategy emerges for each player. In this case, however, imposing stationarity on the differential equat...

In this paper we argue that two important causes of welfare losses in oligopolistic markets have been neglected. We show that in models where location is endogenous, welfare losses arising from wrong locations or from lack of market coverage may be substantial despite firms competing in prices. In contrast, welfare losses arising from quality choice are modest but they might vary discontinuousl...

Competition authorities have a growing interest in assessing the effects of partial ownership arrangements. We show that the effects of such agreements on competition and welfare depend on the intensity of competition in the market and on the firms’ governance structure. When assessing the effects of partial ownership, competition policy has to consider both the financial interest and level of ...

We provide a simple model to investigate decisions about vertical separation. The key feature of this model is that more than one input is required for the final product of the downstream monopolist. We show that as the bargaining powers of independent complementary input suppliers grow larger, the downstream monopolist tends to separate from its input units. The results are related to a visibl...

Theoretically and experimentally, we generalize the analysis of acquiring a company (Samuelson and Bazerman 1985) by allowing for competition of both, buyers and sellers. Näıvety of both is related to the idea that higher prices exclude worse qualities. While competition of näıve buyers increases prices, competition of näıve sellers promotes efficiency enhancing trade. Our predictions are teste...

In this article, we construct a model to study competing payment networks, where networks offer differentiated products in terms of benefits to consumers and merchants. We study market equilibria for a variety of market structures: duopolistic competition and cartel, symmetric and asymmetric networks, and alternative assumptions about consumer preferences. We find that competition unambiguously...

The choice between quantity and price in order to stabilize collusion is modeled here. It is shown that this relocates the prisoners’ dilemma backwards, from the market stage to the stage where the market variable is chosen in order to sustain collusion, and where discount rates appear as the payo¤s. Likewise, a prisoners’ dilemma arises also when both the market variable and the type of behavi...

We reassess the respective gains from R&D cooperation and competition in a Cournot Duopoly with homogeneous goods, where firms adopt a concave cost-reducing R&D technology. Contrary to the previous literature on the same topic, our main results are that (i) no corner solutions emerge and (ii) cooperation, in the form of either a cartel or a joint venture, is always profitable for firms and (iii...