International trade in genetically modified products

This paper investigates competition between two markets that sell close substitutes: a traditional product and a genetically modified (GM) product. Tightening an import quota on the GM product raises the prices of both goods and hurts consumers. Two scenarios are considered under free trade: Cournot–Nash equilibrium and Stackelberg equilibrium. A Stackelberg type monopolist produces more, and the competitive traditional firms produce less, than in Cournot–Nash equilibrium. In the long run, an import ban on the GM product does not help competitive producers of the genetically modified organism (GMO)-free products but benefits only the landowners in Europe.     

Playing Cournot although they shouldn’t

Summary. In this note, we experimentally investigate the extended game with action commitment in a Cournot duopoly with asymmetric cost. Risk dominance considerations allow to select a unique equilibrium in which the low-cost firm is the Stackelberg leader. The data, however, do not support the theory as simultaneous-move play is modal. Average output choices are in line with the Cournot equilibrium. This suggests that Cournot is a much more robust predictor for competition in markets than theory suggests.Received: 14 October 2002, Revised: 1 December 2003, JEL Classification Numbers: C72, C92, D43. Correspondence to: Hans-Theo Normann     

The Optimal Privatization Policies under an International Mixed Duopoly

This paper explores the socially optimal privatization policies under the setting of international mixed duopoly. We find that partial privatization is socially optimal under Cournot competition and private leadership competition, whereas full nationalization is socially optimal under public leadership competition. Moreover, the equilibrium social welfare under private leadership competition is higher than that observed under Cournot competition and that observed under private leadership competition, which differs from the findings of Matsumura ( 2003b ). We also show that the endogenous timing game has a subgame perfect Nash equilibrium outcome, under which the government chooses a partial privatization policy, and private leadership competition emerges as the optimal output decision sequence of firms. An important policy implication from this paper is that the government should partially privatize the public firm and facilitate the emergence of private leadership competition in an international mixed market.     

Asymmetric equilibria under price cap regulation

This study analyzes the effects of a price-cap regulation on market outcomes in Cournot and Stackelberg duopolies. Although two firms are ex-ante identical, there are asymmetric Cournot equilibria as well as the symmetric equilibrium under the price-cap regulation, when the price-cap level is binding. By contrast, the Stackelberg equilibrium is unique and equivalent to the most asymmetric Cournot equilibrium under a binding price-cap level. We present several comparative statics results with respect to the equilibrium outcomes. The main concern of this study is the welfare effect of a change in a price-cap level. We show that when asymmetric Cournot equilibria or the Stackelberg equilibrium are focused on, a reduction in a price-cap level may be socially harmful even if the price-cap level is more than the competitive price.     

Strategic corporate social responsibility,imperfect competition,and market concentration

We examine the strategic use of corporate social responsibility (CSR) in imperfectly competitive markets. Before firms decide upon supply, they choose a level of CSR which determines the weight they put on consumer surplus in their objective function. First, we consider Cournot competition and show that the endogenous level of CSR is positive for any given number of firms. However, positive CSR levels imply smaller equilibrium profits. Second, we find that an incumbent monopolist can use CSR as an entry deterrent. Both results indicate that CSR may increase market concentration. Finally, we show that CSR levels decrease as the degree of product heterogeneity increases in Cournot competition and are zero in Bertrand Competition.     

Competition with Congestible Networks

We analyse competition between two network providers when the quality of each network depends negatively on the number of customers connected to that network. With respect to price competition we provide a sufficient condition for the existence of a unique pure strategy Nash equilibrium. Comparative statics show that as the congestion effect gets stronger quantities will decrease and prices increase, under both Bertrand and Cournot competition. In an example with endogenous capacities it turns out that equilibrium capacities are at first increasing and then decreasing in the strength of congestion. Furthermore, capacities are higher under Cournot competition. Welfare comparisons between Bertrand and Cournot competition are unambiguous for fixed capacities, but may turn around for endogenous capacities.     

Strategic interaction between futures and spot markets

We study an oligopolistic industry where firms are able to sell in a futures market at infinitely many moments prior to the spot market. A kind of Folk-theorem is established: any outcome between perfect competition and Cournot can be sustained in equilibrium. We then find that the Cournot outcome can be sustained by a renegotiation-proof equilibrium. However, this is not true for the competitive outcome. Furthermore, only the monopolistic outcome is renegotiation-proof if firms can buy and sell in the futures market. These results suggest, contrary to existing literature, that the introduction of futures markets may have an anti-competitive effect.     

A note on Stackelberg competition

This note investigates a Stackelberg–Nash competition model. We determine the conditions under which the leaders may achieve better profits than the followers when all firms compete on quantity in a two stage game. We focus on the properties of the followers’ best response functions. It is shown that the Stackelberg equilibrium may coincide with the Cournot equilibrium. In addition, the followers may achieve higher profits than the leaders. Such results put forward the working and the consequences of strategic complementarities. These results are illustrated with three examples.     

The Cournot-Bertrand profit differential: A reversal result in a differentiated duopoly with wage bargaining

This paper compares Cournot and Bertrand equilibria in a downstream differentiated duopoly in which the input price (wage) paid by each downstream firm is the outcome of a strategic bargain with its upstream supplier (labor union). We show that the standard result that Cournot equilibrium profits exceed those under Bertrand competition - when the differentiated duopoly game is played in imperfect substitutes - is reversible. Whether equilibrium profits are higher under Cournot or Bertrand competition is shown to depend upon the nature of the upstream agents’ preferences and on the distribution of bargaining power over the input price. We find that the standard result holds unless unions are both powerful and place considerable weight on the wage argument in their utility function.     

MARKET PRICE MECHANISMS AND STACKELBERG GENERAL EQUILIBRIA: AN EXAMPLE

This paper considers Stackelberg competition in a general equilibrium framework with a productive sector. The working of market power and the configurations of strategic interactions are complexified by the presence of a leader. Two market price mechanisms are studied: one is associated with the Stackelberg–Walras equilibrium and the other is linked to the Stackelberg–Cournot equilibrium. Throughout the example of a two commodity economy, several results are obtained about equilibria mergings and about welfare comparisons.     

Cournot and Stackelberg Duopolies Revisited

First, conditions are derived for a leader (or a follower) to be more advantageous than a follower (or a leader) in Stackelberg duopoly with symmetric firms and without product differentiation. Second, the equilibria in Cournot and Stackelberg duopolies are compared under a set of reasonable assumptions. If the reaction function slopes upward, the Cournot duopolists' profits turn out to be lower than those of both the Stackelberg leader and follower, and the equilibrium industry output is smaller in Stackelberg duopoly than in Cournot duopoly.
JEL Classification Numbers: D21, D43, L13.     

An experiment on learning with limited information: nonconvergence, experimentation cascades, and the advantage of being slow

We present the results of an experiment on learning in a continuous-time low-information setting. For a dominance solvable version of a Cournot oligopoly with differentiated products, we find little evidence of convergence to the Nash equilibrium. In an asynchronous setting, characterized by players updating their strategies at different frequencies, play tends toward the Stackelberg outcome which favors the slower player. Convergence is significantly more robust for a “serial cost sharing” game, which satisfies a stronger solution concept of overwhelmed solvability. As the number of players grows, this improved convergence tends to diminish, seemingly driven by frequent and highly structured experimentation by players leading to a cascading effect in which experimentation by one player induces experimentation by others. These results have implications both for traditional oligopoly competition and for a wide variety of strategic situations arising on the Internet.     

Duopoly competitions with capacity constrained input

This paper focuses on the duopoly substitutability product with an upstream input subjected to capacity constraints. The effects of capacity constraints are captured. Combining competition effect with constraint effect, some interesting conclusions are reached. First, the relationship between capacity constraints and firm size is addressed. We argue that the capacity constraints reduce market size difference and price difference under Cournot. Second, under the Stackelberg case, the existence of solution is proved, and Stackelberg competitions enlarge firm-size difference and price difference if the more efficient firm plays the leading position. When the weaker firm plays the leading position, the conclusions depend on the total capacity. Finally, under the Stackelberg case, when the stronger firm plays the leading position, the firm-size difference and price difference decrease with total input under capacity constraints, which is contrary to the conclusions under Cournot competitions.     

Cournot Duopoly With Multi-period Competition: Inventory as a Coordination Device

This paper analyses a Cournot duopoly model with finitely repeated competition. Each firm is allowed to hold inventories for a period. When there are more than two periods, inventory-holdings encourage firms to take collusive actions. By holding large inventories, a firm can commit to large sales in the next period, giving inventories a strategic value. When a firm deviates from collusion, the strategic value of inventories allows the non-defecting firm to become the Stackelberg leader in future markets, forcing the defecting firm to become the Stackelberg follower. Collusive sales can be attained with this threat of punishment.     

On Stackelberg competition in strategic multilateral exchange

In this paper, we consider a strategic equilibrium concept which extends Stackelberg competition to cover a general equilibrium framework. From the benchmark of strategic market games proposed by Sahi and Yao (1989), we define the notion of Stackelberg equilibrium. This concept captures strategic interactions in interrelated markets on which a finite number of leaders and followers compete on quantities. Within the framework of an example, convergence and welfare are studied. More specifically, we analyze convergence toward the competitive equilibrium and make welfare comparisons with other strategic equilibria.     

ENDOGENOUS TIMING AND STRATEGIC CHOICE: THE COURNOT‐BERTRAND MODEL

Cournot establishes a Nash equilibrium to a duopoly game under output competition; Bertrand finds a different Nash equilibrium under price competition. Both treat the strategic choice variable (output versus price) and the timing of play as exogenous. We investigate Cournot‐Bertrand models where one firm competes in output and the other competes in price in both static and dynamic settings. We also develop a general model where both the timing of play and the strategic choice variables are endogenous. Consistent with the conduct of Honda and Scion, we show that Cournot‐Bertrand behaviour can be a Nash equilibrium outcome.     

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.     

Cartel sustainability with vertical product differentiation: Price versus quantity competition

In the context of a vertically differentiated duopoly, we analyse the influence of the degree of differentiation on cartel sustainability, under both price and quantity competition. We find that, under both Bertrand and Cournot competition, the effect of vertical product differentiation on sustainability of the collusive equilibrium is unclear. It is shown that, given a degree of differentiation, price collusion is more sustainable than quantity collusion.     

Capacity precommitment and price competition yield the Cournot outcome

We introduce a simple model of oligopolistic competition where firms first build capacity, and then, after observing the capacity decisions, choose a reservation price at which they are willing to supply their capacities. This model describes many markets more realistically than the model of Kreps and Scheinkman [Kreps, D., Scheinkman, J., 1983. Quantity precommitment and Bertrand competition yield Cournot outcomes. Bell J. Econ. 14, 326–337]. We show that in this new model every pure strategy equilibrium yields the Cournot outcome, and that the Cournot outcome can be sustained by a pure strategy subgame perfect equilibrium.     

Multinational Corporations, Stackelberg Leadership, and Tariff-jumping

In this paper we consider the traditional entry mode choice of an incumbent monopolist facing entry by a single foreign firm. By allowing entry to be either via exporting or foreign direct investment and for the possibility of Stackelberg equilibria where firms can set quantities in one of two time periods, namely “early” or “late,” we find conditions where both Cournot and Stackelberg equilibria emerge endogenously. Furthermore, by introducing a simple linear tariff, we see that it not only affects the choice of exporting and FDI in a nonlinear way, but that it can also affect the type of equilibrium that emerges.