The Loss from Trade under International Cournot Oligopoly with Cost Asymmetry

This paper examines the efficiency and welfare effects of intra‐industry trade in the presence of imperfect competition and heterogeneous technologies. We show that when a Southern country has a relatively less concentrated industry and faces low demand, the output of the Northern country may contract after initiating trade. Production inefficiencies can outweigh the gain effected by trade‐induced competition and lower price in trade, resulting in a net loss in the global welfare. In some circumstances, voluntary technology transfer, managed trade through VERs, or the introduction of a tariff can improve both trading partners' welfare.     

Unit versus Ad Valorem Taxes in Multiproduct Cournot Oligopoly

The welfare dominance of ad valorem taxes over unit taxes in a single‐market Cournot oligopoly is well known. This article extends the analysis to multimarket oligopoly. Provided all ad valorem taxes are equal and positive, unit costs are constant, firms are active in all considered markets, and a representative consumer has convex preferences, ad valorem taxes are shown to dominate in multiproduct equilibrium. Conditions exist, however, under which economic efficiency declines upon replacing specific taxes with ad valorem taxes that preserve output levels. We discuss the roles of unit cost covariances across multiproduct firms, and also of complementarity in demand, in determining the extent of cost efficiencies arising under ad valorem taxation. For goods that are complementary or independent in demand, conditions are found such that industry profits decline upon use of ad valorem taxes.     

Strategic Investment Subsidies under Asymmetric Oligopoly

This paper examines strategic investment subsidies in an international oligopoly. A general oligopoly model is constructed in which firms compete in two stages and governments commit to investment subsidies prior to firms' actions. The paper considers asymmetry among firms that arises from the nature of goods they produce rather than their cost structures. When firms produce asymmetrically differentiated goods, it is found that a change in the number of foreign competitors may alter the sign of the optimal unilateral investment subsidy. An example of policy reversal is provided in the case of strategic research and development subsidies for a quality‐differentiated industry.     

Information Advantage in Cournot Oligopoly

Consider an oligopolistic industry where firms have access to the same technology but are asymmetrically informed about the environment. Even though it is commonplace to think that in this context superior information leads to higher profits, we find that under Cournot competition this is not generally the case: It holds when firms' technology exhibits constant returns to scale, but it does not necessarily hold otherwise. Journal of Economic Literature Classification Numbers: C72, D43, L13.     

Mergers and Trade Policy under Oligopoly

For an oligopolistic industry, the effects of mergers on the domestic country's optimal trade policy are analyzed. If the domestic country pursues an optimal trade policy then it will always lose as a result of a foreign merger. The optimal domestic response to a foreign merger is to decrease (increase) the tariff if demand is concave (convex) and to increase the production subsidy. The foreign merger reduces foreign welfare when the domestic country pursues its optimal trade policy. The optimal domestic response to a domestic merger is to leave the tariff unchanged and to increase the production subsidy.     

Relative Emission Standard versus Tax under Oligopoly: The Role of Free Entry

We compare the effects of an emission tax, and those of a relative emission standard, on welfare and pollution levels under oligopolistic market structures. We consider the cases where the number of firms is fixed and where there is free entry and exit of firms. When the number of firms is fixed, (i) a relative emission standard is welfare-superior to an emission-equivalent emission tax, and (ii) an emission tax is emission-superior to a welfare-equivalent relative emission standard. Under free entry and exit, the results are just the opposite when the inverse demand function is concave.     

Piecemeal Multilateral Environmental Policy Reforms under Asymmetric Oligopoly

We develop a general two‐country model with oligopolistic interdependence in which a fixed number of firms make their output and emission decisions simultaneously. We examine the effect of multilateral reforms of emission taxes on global emission levels. With sufficient asymmetry in pollution intensities between the two countries, a proportional multilateral increase in emission tax rates can increase global emission levels. However, a multilateral equal increase of emission tax rates unambiguously reduces global emission levels. We also consider the case of free entry and exit of firms, and find a rule of multilateral reforms which unambiguously lowers total emission levels.     

Gains from Trade in a Differential Game Model of Asymmetric Oligopoly

This paper revisits a classical topic of trade gains in a differential game model of oligopoly in which Home and Foreign firms differ in the number and cost. After deriving the feedback Nash equilibrium, we provide examples to consider how the difference in the number of firms or costs affects gainfulness of trade. We prove that feedback strategies can result in implications for trade gains which are sharply different from the open-loop case.     

A Cournot Mechanism for Pollution Control under Asymmetric Information

The contribution of this paper is to show that a simple nonlinear tax can achieve a long-run socially optimal level of pollution without the regulator knowing marginal abatement costs. Firms are charged their differential contribution to total damages, evaluated at the upper margin of current emissions. This induces a Cournot game in pollution levels. We show that the Nash equilibrium exists, corresponds to the socially optimal long-run output and emission levels and number of firms, is stable, and can be reached by iterative computations where conjectures are formed using a linear estimator based on past emission levels.     

Cournot Oligopoly and the Theory of Supermodular Games

We reconsider the Cournot oligopoly problem in light of the theory of supermodular games. Invoking the recent ordinal version of this theory proposed by Milgrom and Shannon, we generalize Novshek's existence result, derive the associated uniqueness result, give an extension of a classical existence result under symmetry, and provide conditions making a Cournot oligopoly into a log-supermodular game (with the natural order on the action sets). We also provide extensive and precise insight as to why decreasing best-responses are widely regarded as being “typical” for the Cournot model with production costs. Several illustrative examples are provided.Journal of Economic LiteratureClassification Numbers: C72, L10, L13.     

Welfare Effects of Commodity Taxation in Cournot Oligopoly

In the context of Cournot oligopoly with possibly asymmetric costs, this paper presents necessary and sufficient conditions for a small specific tax and a small ad valorem tax to increase total surplus. The paper also shows that a shift from a small specific tax to a small ad valorem tax, leaving the tax revenue unchanged, increases the total surplus.
JEL Classification Numbers: D43, H21, L13.     

Learning in Cournot Oligopoly – an Experiment

This experiment was designed to test various learning theories in the context of a Cournot oligopoly. We derive theoretical predictions for the learning theories and test these predictions by varying the information given to subjects. The results show that some subjects imitate successful behaviour if they have the necessary information, and if they imitate, markets are more competitive. Other subjects follow a best reply process. On the aggregate level we find that more information about demand and cost conditions yields less competitive behaviour, while more information about the quantities and profits of other firms yields more competitive behaviour.     

Quasi-Competitive Cournot Oligopoly with Product Differentiation and Symmetric Firms

Since Vives (1984 ), Cheng (1985 ) and Okuguchi (1987 ), the equilibria in Bertrand and Cournot oligopolies with product differentiation have been known to differ. Okuguchi (2005 ) has shown that Bertrand price‐adjusting oligopoly with product differentiation and symmetric firms is quasi‐competitive but not perfectly competitive in the limit state of infinite number of firms. This paper formulates and analyzes two types of Cournot output‐adjusting oligopoly with product differentiation and symmetric firms, in one of which symmetric firms producing the same goods are assumed to collude, and in the other, collusion is ruled out. The limit states are shown to be different in two oligopolies but they are both quasi‐competitive.     

Stackelberg versus Cournot Equilibrium

We reconsider Stackelberg's classical critique of the Cournot duopoly, in the framework of endogenous timing for two-player games. For quantity duopoly we provide different sets of minimal conditions, directly on the demand and cost functions, yielding respectively the simultaneous and the two sequential modes of play. While our findings essentially confirm the predominance of the former, they also indicate that the latter is natural under some robust but restrictive conditions. No extraneous assumptions (such as concavity, existence, or uniqueness of equilibria…) are needed, and the analysis makes crucial use of the basic results from the theory of supermodular games.Journal of Economic LiteratureClassification Numbers: B21, C72, D43, L13.     

Bertrand versus Cournot revisited

Summary. Bertrand criticized Cournot's analysis of the competitive process, arguing that firms should be seen as playing a strategy of setting price below competitors' prices (henceforth, the Bertrand strategy) instead of a strategy of accepting the price needed to sell an optimal quantity (the Cournot strategy). We characterize Nash equilibria in a generalized model in which firms choose among Cournot and Bertrand strategies. Best responses always exist in this model. For the duopoly case, we show that iterated best responses converge under mild assumptions on initial states either to Cournot equilibrium or to an equilibrium in which only one firm plays the Bertrand strategy with price equal to marginal cost and that firm has zero sales. Received: December 11, 1995; revised version October 2, 1996     

The Complete Welfare Effects of Cost Reductions in a Cournot Oligopoly

This paper provides the smallest upper bound or the critical level for a Cournot firm's market share below which its cost reduction reduces welfare. It shows that a firm's cost reduction increases social welfare with nonlinear demand and nonlinear costs if and only if its market share is above the critical level, which is equal to a weighted sum of the other firms' market shares. The paper also reports similar results for technological spill-overs within any given set of firms.     

On the Uniqueness of Equilibrium in Cournot Oligopoly and Other Games

In an average surplus sharing game, such as a Cournot oligopoly, a group of agents share a production process. Each contributes an amount of input to the process, and output is divided in proportion to the amount of input contributed. Uniqueness of the equilibrium is needed for any type of comparative static analysis. However, general uniqueness results for concave games have restrictive assumptions on preferences and technology; specifically, the conditions needed for uniqueness become more difficult to meet as the number of players increases. A new theorem for uniqueness with easily interpretable conditions is given which is independent of the number of players.Journal of Economic LiteratureClassification Numbers: C70, C72, D43.     

Mixed Oligopoly at Free Entry Markets

We investigate the optimal behavior of a public firm in a mixed market involving private firms and one public firm. Existing works show that welfare-maximizing behavior by the public firm is suboptimal when the number of firms is given exogenously. We allow free entry of private firms and find that, in contrast to the case with the fixed number of firms, welfare-maximizing behavior by the public firm is always optimal in mixed markets. Furthermore, we find that mixed markets are better than pure markets involving no public firm if and only if the public firm earns nonnegative profits.     

Preferential Trade Liberalization Under Cournot Competition

Suppose a country imports a homogeneous good from n foreign countries/producers and wants to eliminate tariffs on imports from m < n of them. If foreign producers differ in their marginal costs, which ones will be among the m that are granted free trade? This paper shows, among other things, that under constant marginal cost and fairly general assumptions about demand it will be the least efficient producers.