Domestic entry, optimum-welfare and maximum-revenue tariffs

In this paper, we examine the ranking of the maximum-revenue tariff and the optimum-welfare tariff under a linear Cournot oligopoly model without and with free entry of domestic firms. We demonstrate that in a regulated entry oligopoly with asymmetric costs, when the marginal cost of the domestic firms exceeds a critical value, the maximum-revenue tariff is higher than the optimum-welfare tariff. We then show that under free entry of domestic firms with asymmetric costs, when the fixed cost gets larger and the domestic firms become fewer, the difference between the optimum-welfare tariff and the maximum-revenue tariff becomes larger.     

Free and second-best entry in oligopolies with network effects

We compare the number of firms in equilibrium in a Cournot industry with positive network effects and complete compatibility, under free and second-best entry. Under free entry, the firms decide whether to enter the market or not; in the second-best problem, the number of firms is established by the regulator to maximize social welfare (the regulator controls entry but not production). We show that when individual equilibrium output decreases with entry (business-stealing competition), free entry may lead to more or less firms than the second-best problem. This contrasts with the standard (nonnetwork) Cournot oligopoly model, wherein with business-stealing competition, free entry leads to an excessive number of firms compared with the second-best solution.     

Price and quantity competition under free entry

This paper complements that of Cellini et al. (Cellini, R., Lambertini, L., Ottaviano, G. I. P., 2004. Welfare in a differentiated oligopoly with free entry: A cautionary note. Research in Economics, 58:125–33.), which shows that Cournot competition may generate higher welfare compared to Bertrand competition in an economy with free entry. Unlike them, we provide a more general proof for this result and show that Cournot competition generates higher welfare compared to Bertrand competition when the products are sufficiently differentiated. If the products are close substitutes, welfare is higher under Bertrand competition. We show that these qualitative results hold whether or not number of varieties increases market size. We also show when the active firms earn higher profits under Bertrand competition compared to Cournot competition.     

Reexamination of Strategic Public Policies

This paper attempts to reinterpret the familiar approach to strategic public policies from the viewpoint of inefficiencies involved in oligopoly where firms engage in Cournot competition. To this end, we introduce tools called “quasi‐reaction functions” and “quasi‐supply curves”. These tools allow us to conduct analyses through use of the standard partial‐equilibrium diagram, i.e. the quantity‐price plane. We can find the relationship between prices and quantities directly and, hence, deal with inefficiencies easily and also suggest policies to correct such inefficiencies. Specifically, we reexamine public policies related to mixed‐oligopoly, excess entry, technology choices with free entry and exit, and foreign oligopoly.     

Comparison between specific taxation and volume quotas in a free entry Cournot oligopoly

We revisit the classic discussion of the comparison between tax and quota, but in a free-entry Cournot oligopoly. We investigate a quantity ceiling regulation as a quota policy. We find that tariff-quota equivalence holds if the firms are symmetric and the number of firms is given exogenously. However the equivalence does not hold and taxes dominate quotas in the free entry market because quota can increases the number of entering firms and increases the loss caused by excessive entries.     

Labor-managed Cournot oligopoly and industry output

It is known that in imperfectly competitive situations a labor-managed firm produces less output than an equivalent entrepreneurially controlled firm. However, it has also been suggested that there would be more labor-managed firms than entrepreneurial firms, ceteris paribus. Analysis shows that, in the context of a Cournot model of oligopoly with free entry, the latter contention is false, so the labor-managed industry would not be “more competitive.” Some extensions and comments on this result are also offered.     

Environmental protection without loss of international competitiveness

We develop a two‐country Cournot oligopoly model with product differentiation across countries and production‐generated pollution. The abatement of pollution by the firms in response to emission taxes is endogenous, and the number of firms can be fixed or there may be free entry and exit of firms in both countries. We propose particular unilateral and multilateral piecemeal policy reforms of emission taxes and production subsidies such that domestic industries will not suffer any loss of international competitiveness (defined in terms of either market share or profits), emission levels will be lower, and welfare could be higher in both countries.     

Bilateral oligopoly and quantity competition

Bilateral oligopoly is a market game with two commodities, allowing strategic behavior on both sides of the market. When the number of buyers is large, bilateral oligopoly approximates a game of quantity competition played by sellers. We present examples which show that this is not typically a Cournot game. Rather, we introduce an alternative game of quantity competition (the market share game) and, appealing to results in the literature on contests, show that this yields the same equilibria as the many-buyer limit of bilateral oligopoly, under standard assumptions on costs and preferences. We also show that the market share and Cournot games have the same equilibria if and only if the price elasticity of the latter is one and investigate the differences in equilibria otherwise. These results lead to necessary and sufficient conditions for the Cournot game to be a good approximation to bilateral oligopoly with many buyers and to an ordering of total output when they are not satisfied.     

Is a Unique Cournot Equilibrium Locally Stable?

We consider a homogeneous product oligopoly, where the Cournot equilibrium is regular and unique. We show that for a duopoly, a unique Cournot equilibrium is always locally stable. For a “n” firm asymmetric cost oligopoly a unique Cournot equilibrium is locally stable under very general conditions. The sufficient conditions for local stability of a unique Cournot equilibrium are much less restrictive than what the existing literature suggests. For a symmetric cost oligopoly the unique Cournot equilibrium is almost always locally stable, except for a perverse case. Journal of Economic Literature Classification number: L13.     

THE MARKET SELECTS THE WRONG FIRMS IN THE LONG RUN*

We consider the effects of free entry on the market structure and social welfare of an asymmetric Cournot oligopoly. Even if we allow for the existence of different types of firms initially, only one type (in almost all cases) can survive in the long run. Free entry leads an economy to a symmetric equilibrium, in which the excess entry theorem holds. Further, we consider the socially optimal policy for this economy. In cases of either (i) a concave demand (which implies strategic substitutability) or (ii) strategic complementarity (which implies a convex demand), the type of firms that should remain in the market to achieve social optimality does not necessarily coincide with the type of firms that will survive in the long run. The market may select not only the wrong number of firms but also the wrong type of firms in the long run.     

Taxation within Cournot oligopoly

When the production of output causes pollution, we often consider taxation as a means to reduce it. This paper examines various forms of taxation to control pollution within Cournot oligopoly. It shows that two commonly used forms can actually increase pollution. In contrast, both of these forms unambiguously reduce pollution within the competitive model. The paper provides conditions, in terms of demand and technology, that make taxation effective in the Cournot oligopoly case. Another implication of the analysis is that, outside the price-taking framework, asymmetry of cost functions is particularly important and deserves careful attention when we examine the effect of taxation.     

Trade liberalization in a differentiated duopoly reconsidered

Constructing a model of differentiated Cournot duopoly, we consider welfare effects of trade liberalization (i.e. reductions in transport costs). We examine both multilateral trade (i.e. the firms in both countries export bilaterally) and unilateral trade, under which foreign entry is possible but the home firm cannot export. Some new results on trade gains under differentiated oligopoly are proved and their implications are discussed.     

On the Uniqueness of the Welfare–maximizing Number of Firms Under Cournot Oligopoly

Under Cournot oligopoly with a homogeneous product, we present a sufficient condition that guarantees the uniqueness of the welfare–maximizing number of firms to attain the global maximum level of welfare by implementation of a piecemeal policy changing the number of firms gradually. We adopt Selten's (1973) 'fitting–in function' method, which relates an individual firm's output to an industry's output. When the number of firms is unique, then introducing a lump–sum profit tax (subsidy) can attain the optimal level of welfare. Indirect entry regulation is superior to direct entry regulation from the standpoint of welfare if each entrant engages in rent–seeking activities.     

The welfare effects of entry: the role of the input market

In a successive Cournot oligopoly, we show the welfare effects of entry in the final goods market with no scale economies but with cost difference between the firms. If the input market is very concentrated, entry in the final goods market increases welfare. If the input market is not very concentrated, entry in the final goods market may reduce welfare if the entrant is moderately cost inefficient. Hence, entry in the final goods market is more desirable if (1) the input market is very concentrated or (2) the cost difference between the incumbents and the entrant is either very small or very large. It follows from our analysis that entry increases the profits of the incumbent final goods producers if their marginal costs are sufficiently lower than the entrant’s marginal cost.     

Inferior factor in Cournot oligopoly

The condition for factor inferiority has been well known for a competitive firm facing perfect competition in both product and factor markets. Whether the factor inferiority is observable or not has been unknown for oligopoly facing perfect competition in factor market. We derive a general condition for the factor inferiority in Cournot oligopoly without product differentiation. We derive it on the basis of a novel technique for proving the existence of a unique Cournot equilibrium industry output.     

A Note on Production Efficiency in Oligopolistic Trade Models

In a two‐country segmented markets model with homogeneous product Cournot oligopoly we show that production efficiency improves in the free‐trade regime compared to autarky, if autarky price in each country is lower than both the post‐trade prices—which holds, for example, when preferences are identical. The result holds irrespective of the demand structure, number, and cost distribution of firms in the two countries. The improvement in production efficiency lowers average cost of production which, for some parameterizations, gives rise to higher aggregate profits for all countries in the free‐trade regime (compared to autarky). Though free trade (zero tariffs) improves production efficiency from autarky (prohibitive tariffs), freer trade is not always associated with greater production efficiency.     

INSUFFICIENT ENTRY OF EMPLOYEE‐CONTROLLED FIRMS IN A FREE‐ENTRY OLIGOPOLY

This study is a theoretical examination of whether employee‐controlled firms (ECFs) enter a free‐entry oligopolistic market excessively or insufficiently, from the viewpoint of welfare maximization. The excess entry theorem is well known in oligopoly theory. According to this theorem, a greater number of profit‐maximizing firms enter a free‐entry oligopolistic market than is optimal for welfare maximization. We demonstrate the possibility that insufficient entry arises when ECFs compete in a free‐entry market. In particular, we show that if both the demand and cost functions are convex, insufficient ECF entry necessarily occurs. Our results suggest that competition among firms seeking purposes other than profit might lead to insufficient entry because differences in competing firms’ objectives affect the intensity of market competition.     

Firm Scale and the Endogenous Timing of Entry: a Choice between Commitment and Flexibility

This paper presents a model of stochastic oligopoly with demand uncertainty where firms endogenously choose entry timing. We examine two extreme types of market structure and show that the equilibrium correspondence that connects them is continous. With two identically sized firms, there are symmetric, Cournot type equilibria where the probability of early entry declines with greater uncertainty, and for low uncertainty two asymmetric equilibria. With one large firm with a continuum of nonatomic firms, there is a unique Stackelberg equilibrium. We conclude that the behavior of a dominant firm with a finite fringe can be approximated by Stackelberg equilibrium.Journal of Economic LiteratureClassification Numbers?: D21, L11.     

INFINITE ASYMMETRIC EQUILIBRIA IN MIXED OLIGOPOLIES

We show that infinite asymmetric equilibria may be supported in a mixed Cournot oligopoly with identical private firms. This sharply contrasts with the case of private Cournot oligopolies, where only symmetric equilibria arise.     

Price formation in heterogeneous oligopoly

Conclusion An equilibrium price vector has been defined and its existence and function in static price formation in cases of heterogeneous oligopoly has been established. Hitherto, authors have been misled, we think, by misinterpreting the role of reaction functions, which are central to our argument. After defining and proving the existence and uniqueness of an equilibrium price vector, it is possible to construct a generalization of the wellknown equilibrium concept of the Nash-Cournot game solution. It has previously been thought that the restriction to the Cournot solution is one of the main drawbacks to using game theoretical solutions to the problem of oligopoly. We have developed a generalization of the Nash solution in order to deal with a type of reaction hypothesis which cannot be expressed in terms of the Cournot reaction function. The new set of reaction functions here introduced demonstrate conclusively that the so-called identity on a Nash and a Cournot equilibrium is only of a formal character.We would like to thank F. Delbaen, R. A. Hirschfeld and K. Okuguchi for useful comments on an earlier draft of this paper.