Mixed Duopoly and Environment

We show under general demand and cost conditions that in a mixed duopoly with pollution the government can implement the socially optimal outputs and abatements by a tax‐subsidy scheme and keeping the public firm fully public. The scheme requires taxing outputs and subsidizing abatements at different rates, unlike a pollution tax. Our result improves on the shortcoming of a pollution tax to implement the social optimum. We also show that when the private firm is partly foreign‐owned, the government will adopt some privatization and will not implement the social optimum, though the social optimum is implementable.     

Duopoly signal jamming

Summary This paper examines a repeated duopoly market with heterogeneous outputs. Firms have (common) prior beliefs over the values of an unknown parameter of each firm's demand curve. Firms cannot observe rivals' quantities, but can observe market prices, which are subject to random disturbances and hence provide noisy information that firms use to update their beliefs concerning the unknown parameters' values. Each firm can potentially signal jam, or strategically vary its output level in order to manipulate the distribution of likely market prices and hence the likely inferences drawn by the opponent. We find that the opportunity to signal-jam introduces two conflicting effects, arising out of the desire to manipulate expectations concerning each of the two demand curves. Depending upon the relative magnitudes of these two effects, signal-jamming may lead firms to either increase or decrease period-one quantities. If the firms are symmetric, then the opportunity to signal jam induces both firms to increase output in order to induce their rival to conclude that demand is unfavorable. However, if the firms believe almost surely that one of the possible parameter values is true for firm 2's demand curve (for example), then firm 1 may signal-jam by producing less output.We thank two anonymous referees, an associate editor and Pieter Kop Jansen for helpful comments that corrected some errors. Larry Samuelson is grateful to the Center for Economic Research at Tilburg University and the Department of Economics at the University of Bonn for support. Financial support by the Deutsche Forschungsgemeinschaft (DFG) through Sonderforschungsbereich 303 is gratefully acknowledged.     

Bowley Duopoly Under Vertical Relations

Compared to the well‐known oligopoly models such as those of Cournot, the so‐called Bowley duopoly is less known, and almost ignored in the literature. This neglect reflects the assumption that as a leader–leader model incorporating apparent excess rivalry it is presumably untenable, at least in theory. However, it is, in fact, observable in practice. Furthermore, the predicted excess competition is not only observable empirically but also accountable theoretically. We show how excess competition emerges when an upstream monopolist offers the downstream retailers a compensated game in which each acts as a leader. The outcome is not only stable but also benefits all involved actors, including consumers under vertically‐related markets, such as those presided over by a monopolist producer. This result of emergent stability shows that the Bowley duopoly should be considered alongside other oligopoly models.     

The Chamberlin and Stackelberg Duopoly Relation*

The paper investigates and identifies an important relationship between the Chamberlin and Stackelberg duopoly models. Under conditions of symmetry, linear demand and constant costs, the two iso-profit curves identifying the Stackelberg leadership points are shown to be tangent at the Chamberlin point. Under these conditions profit-maximising duopolists are indifferent to being Stackelberg output leaders and coalescing in an equal-shares-joint-monopoly solution. This result is shown to be sensitive to the constant cost and linear assumptions. Under increasing linear marginal costs, the joint monopoly solution is preferred by both sellers to a leader-follower solution.     

Technical Improvements and Welfare under International Duopoly

It is now common wisdom that a free-trading country with perfectly competitive markets might be hurt by its own technical improvement of that country's export industry, and that an improvement in the import-competing industry never impoverishes the country if no commodity is inferior for that country. This paper examines the welfare effects of technical progress in a perfectly competitive industry and in an internationally duopolistic market in a two-country, two-good, one-factor trading model. It will be shown that the above propositions are severely qualified in our setting with duopolistic industry.     

Mixed Duopoly,Merger and Multiproduct Firms

The literature on mergers has extensively analyzed the decision to merge by private firms, but it has not considered the decision to merge by private and public firms. We assume that when a private firm and a public firm merge (or when one of them acquires the other), they set up a multiproduct firm in which the government owns an exogenous percentage stake. In this framework, we show that the decision to merge by firms depends on the degree to which goods are substitutes and on the percentage of the shares owned by the government in the multiproduct firm.     

Unionized Bertrand Duopoly and Strategic Export Policy

The paper reports that an export subsidy is optimal for a unionized Bertrand duopoly. Following results published by Brander and Spencer ( Journal of International Economics , 1988, pp. 217–34), this establishes the robustness of export subsidization to the mode of competition (Cournot or Bertrand), and contrasts with nonunion results in the literature. If both firms are unionized and both governments pursue active trade policies, a subsidy remains optimal except for a narrow range of extreme substitutability between products. Nations with a lower opportunity cost of labor employ more aggressive policies in equilibrium.     

Perpetual Leapfrogging in Bertrand Duopoly

We consider different patterns of infinite technological adoption choices by firms in a Bertrand duopoly. Every period technological progress provides a sequence of cost reducing innovations. The equilibrium concept is Markov perfect equilibrium. We analyze conditions for which equilibrium adoption leads to persistent leadership and those where firms alternate in adoption inducing leapfrogging. Only leapfrogging leads to technological improvement in the long run. Demand conditions play a crucial role in determining whether leapfrogging can be perpetual in Bertrand duopoly.     

Delegation and Information Sharing in Cournot Duopoly

Information sharing in oligopoly has been analyzed by assuming that firms behave as a sole economic agent. In this paper it is assumed that ownership and management are separated. Contrary to the classical result of information sharing in a Cournot duopoly with private cost information, the paper shows that information sharing is no longer always a dominant strategy and expected consumer surplus is no longer always decreased. The paper determines the circumstances under which information is exchanged and analyzes its welfare consequences.      

Environmental Taxation and Strategic Commitment in Duopoly Models

In this paper, we address the issue of optimalenvironmental taxation under imperfect competition.The problem is analysed for three different types ofduopoly models, the Cournot open and closed loopmodels, and the Stackelberg model. We explicitlyanalyse the role of strategic behaviour. Each firm hasto make a choice of output level and of the level ofa strategic variable. The choice of this strategicvariable affects both marginal cost and emissions. Wecompare the properties of these three duopoly models,and derive and compare optimal environmental taxes. Weshow that whether the optimal tax is lower or higherthan marginal environmental costs depends on theinformation transmission and the effect of thestrategic variable on marginal costs. In addition, thedifferences in market shares, and the influence of thetax on the cost structure play important roles, indetermining optimal emission taxes.     

Market Instability in a Stackelberg Duopoly

m -period duopoly model with inventory costs, where each firm chooses when to produce. We find that, in contrast to most existing works concerning endogenous roles of the firms, no pure strategy equilibrium exists when m is strictly larger than two. This result indicates that no stable pattern of allocation of roles exists except for a two-period model; thus the leader-follower relationship inevitably becomes instable. Received August 1, 2000; revised version received July 20, 2001     

Real Option and Strategic Decision Making of Duopoly

Other than traditional valuation methods, the real option approach captures the flexibility inherent in investment decisions to make the optimal decision of a finn in isolation from its competitors. In reality, however, the actions or decisions of competing fn-ms （practical or potential） often affect each other＇s investment opportunity. The value of the project for the firms is assumed to follow a Geometric Brownian motion, and the model combines game theory and the theory of irreversible investment under uncertainty. This paper characterizes the resulting Nash equilibrium under different assumptions on the information that the firms have each other＇s valuation for the project.     

Exploring Duopoly Markets with Conjectural Variations

In this article, the authors investigate competitive firm behaviors in a two-firm environment assuming linear cost and demand functions. By introducing conjectural variations, they capture the different market structures as specific configurations of a more general model. Conjectural variations are based on the assumption that each firm believes its own strategy influences its rival's strategy. Firms derive their optimal choice from these exogenous conjectures, under the form of a conjectural best-response function. The authors’ approach fully encompasses the standard measures of market power (the Lerner Index) and concentration (the Herfindahl Index), both depending on the conjectural variations. They finally represent, analytically and graphically, the equilibrium strategies and the associated indexes in a unified framework for any level of competition, ranging from perfect competition to collusion.     

A Mixed Duopoly With Switching Costs

We examine the effects of switching costs in a two‐period Hotelling‐type model where a profit‐maximising private firm competes with a welfare‐maximising public firm. We show that, in contrast with the case in which both firms are private, where switching costs raise prices in both periods, in the mixed duopoly they raise prices in the second period but reduce them in the first period. Moreover, the first‐period price reduction is of such magnitude that switching costs reduce firms’ profits and raise consumer welfare. We also find that switching costs affect the consequences of privatisation in favour of firms and against consumers.     

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.     

Stackelberg竞争条件下的最佳福利关税与最大收入关税

文章考察Stackelberg竞争条件下的最佳福利关税与最大收入关税。分析表明,最佳福利关税与最大收入关税的相对大小主要取决于产品之间的相互关系和国内外企业的成本差异。当产品是互补品时,最佳福利关税总是小于最大收入关税;当产品是替代品时,最佳福利关税与最大收入关税的关系,既取决于产品间的替代程度又取决于国内外企业间的成本差异。产品的替代程度较弱时,最大收入关税总是大于最佳福利关税;产品的替代程度较强时,若国内外厂商间的成本差异越小,则最佳福利关税越有可能超过最大收入关税。     

Duopoly compatibility standards with partial cooperation and standards leadership

This paper presents a model of duopolists producing differentiated substitutes. Greater compatibility between the products causes each to have a greater demand. However, each firm has a most desired location in the product space (a most preferred technical standard); deviation from that standard in the direction of the rival's standard increases compatibility, but is costly. This paper presents the equilibrium outcomes for two products under Cournot rivalry, multiproduct monopoly, second-best standards-specification, and welfare maximization. The outcome associated with partial cooperation is examined. Then the Stackelberg model is used to derive the equilibrium conditions for output leadership and technical standards leadership. This model of technological externalities allows us to compare and evaluate different standards-specification processes.     

转移成本、价格歧视和非对称寡头竞争

通过在Hotelling空间差异模型的基础上结合转移成本构建非对称企业竞争博弈模型.主要研究在非对称情况下,两企业在一致定价与价格歧视下竞争的均衡结果.还对两种不同定价体制下的均衡结果进行了比较,分析价格歧视是否强化竞争.研究发现价格歧视对竞争的效应是不确定的,很大程度受到两企业不对称程度的影响.