Mixed Market Competition in a Quality Differentiated Duopoly Model An Approach to Banking Sector

This paper attempts to develop a theoretical framework to investigate the competitive implications of quality choices of financial institutions whereby they charge prices to consumers based on their willingness to pay for the service qualities in the mixed market scenario under vertical product differentiation model. Initially, it analyzes benchmark equilibrium solutions of monopoly and duopoly to establish the degree of quality differentiation between two private banks in an uncover market configuration. Further, it estimates the quality differentiation between private and public banks, and examines the interaction between two market structures keeping public bank as both leader and follower, and then measures the social welfare from different prospectives. The explicit operation of two stages Nash equilibrium game forecasted that public banks＇ monopoly seems to be still better than a private banking, and it is socially optimal. The outcome demonstrates a significant importance of vertical quality differentiation for policy implication in banking industry and provides an insight on the reasons of particular co-existence of public and private banking services in the specified location. In this context, it is concluded that the presence of public banks in banking industries is a crucial condition for obtaining the higher range of social welfare.     

Foreign market entry,upstream market power,and endogenous mode of downstream competition

In a differentiated duopoly model of trade and FDI featuring both horizontal and vertical product differentiation, we examine whether globalization and trade policy measures can generate welfare gains by leading firms to change their mode of competition. We show that when a high-quality foreign variety is manufactured under large frictions due to upstream monopoly power, a foreign firm can become a Bertrand competitor against a Cournot local rival in equilibrium, especially when the relative product quality of the foreign variety is sufficiently high and trade costs are sufficiently low (implying higher input price distortions due to double marginalization). Our results suggest that such strategic asymmetry is welfare improving and that the availability of FDI as an alternative to trade can make welfare-enhancing strategic asymmetry even more likely, especially when both input trade costs and fixed investment costs are sufficiently low and trade costs in final goods are sufficiently large.     

PROFITABLE STRATEGIC DELEGATION WITH CONJECTURAL VARIATIONS

Firms delegate strategic decisions to managers because they find it profitable to do so. In the product market, when agents make conjectures about the reaction of their rivals to marginal changes in their own strategies, the set of equilibriums can be enlarged with respect to the case of no conjectures. This paper takes a duopolistic linear market parameterization where firms selling differentiated products can delegate either price or output decisions to managers. We show that it is a dominant strategy for firms to delegate no matter whether firms are Cournot or Bertrand competitors, although the equilibrium is not necessarily efficient. Futhermore, in equilibrium Cournot competition is more profitable for firms than Bertrand competition. Finally, requiring consistency in conjectures yields the same outcome no matter what type of strategic interaction and managerial choice there is on the part of firms.     

产品差别化、价格战与合谋

随着中国市场化改革的不断深入,价格战成为各行各业企业间不断上演的舞台剧。文章旨在从产品差别化与企业间合谋的相互关系出发,来分析企业频繁选择价格竞争而难以进行合谋的原因,即产品垂直差别水平的降低将使合谋难以维持,价格战容易爆发。因此,解决价格战的途径之一是中国企业应该加大自主创新的能力,提高产品垂直差别化程度。     

Optimal pollution taxation in a Cournot duopoly

It is well known that the optimal pollution tax in a competitive industry is equal to the marginal damage inflicted by the pollution. It has also been shown that the optimal pollution tax on a monopoly is less than the marginal damage. In this paper, I derive the optimal pollution tax for a Cournot duopoly. If firms have different production costs, the optimal tax rate may exceed the marginal damage. This is so because the tax may be an effective instrument for allocating production from the less to the more efficient firm. It is also shown that, if one firm has a positive most preferred pollution tax, the sum of consumer and producer surpluses will be declining in the tax at this level.     

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.     

Biased managers with network externalities

In network industry under Cournot and Bertrand competition, we examine a model when owners of firms hire biased managers who have incorrect market demand. Contrast to previous studies, we show that (i) regardless of the strength of network externalities when consumers form the responsive and passive expectations, owners realize strategic advantage by hiring biased managers to be more aggressive under Cournot and Bertrand competition, (ii) firms prefer facing passive expectations for the weak network externalities and vice versa for the strong network exteranlities under Bertrand and Cournot competition, (iii) if the network size is sufficiently large, then the prisoner's dilemma that firms hire aggressive managers no longer exists under both competition modes. As with no delegation case, we obtain the different rankings of firms' profit depending on both network externalities and forming of expectations under Cournot and Bertrand competition.     

Tacit Collusion in a Spatial Model with Delivered Pricing

Received August 5, 1999; revised version received July 20, 2001     

一个具有双寡头垄断性质的三边贸易模型——以石油市场为例的国家福利实验模拟分析

中国作为大宗商品的国际大买家,争取国际定价权已经成为再也无法回避的问题.有鉴于此出,文章以石油为例,着重探讨石油定价战略选择的经济学机理,在一个具有双寡头垄断性质的三边贸易体系中,对OPEC和非OPEC石油输出国之间的博弈进行了一般均衡分析.根据模型设定参数及实验模拟发现,在Cournot双寡头垄断下,国家M的福利水平增加32.4%,而国家F的福利水平却下降0.8%.由此作出的解释是:与M相反,F是石油净进口国家,高油价和商品y较低的相对价格所产生的负面效应要大于闲暇带来的正面效应.此时,整个社会福利下降0.7%.石油在消费者效用函数中的权重较小时,石油生产的一个负向冲击对福利损失的影响非常有限.在F和M的纯策略集合{双寡头垄断,完全竞争,不生产石油}中,存在唯一的纳什均衡{完全竞争,完全竞争},这使得国家H和F从中获益.模型给人的启示是,除了尽快完善国家石油战略储备体系外,中国应积极参与到石油定价权的争夺中,改变目前完全被动承受油价变动影响的不利地位.     

Price versus quantity in a mixed duopoly with foreign penetration

We characterize the endogenous competition structure (in prices or quantities) in a differentiated duopoly between a public firm that maximizes domestic welfare and a private firm that can be owned by domestic or foreign investors. The market for which they compete can be domestic or integrated: in the first case Bertrand competition emerges endogenously and in the second case Cournot competition can emerge if the fraction of domestic consumers in the integrated market is low enough. We also determine the optimal degree of foreign penetration showing the optimality of a partial foreign ownership. Finally, we extend the model to increasing marginal cost confirming the robustness of the results.     

Subsidizing cooperative and noncooperative R&D in duopoly with spillovers

Comparing the effect on private R&D investments of allowing firms to cooperate in R&D with that of providing R&D subsidies reveals that in general the latter policy is more effective than the former in promoting R&D activity. Analyzing the implementation of both policies simultaneously reveals that subsidizing cooperative and noncooperative R&D leads to the same market outcome. The preferred R&D-stimulating policy is to subsidize optimally an agreement according to which firms only share the outcomes of their independent research.     

On the efficiency of indirect taxes in differentiated oligopolies with asymmetric costs

This paper shows that unit taxation can be welfare superior to ad valorem taxation in asymmetric and differentiated oligopolies if the goods are sufficiently differentiated, the cost variance is sufficiently large and the ad valorem tax rate is sufficiently high. Moreover, this result holds under either Cournot competition or Bertrand competition.      

Minimum Quality Standards under Asymmetric Duopoly with Endogenous Quality Ordering: A Note

In this note, we revisit minimum quality standards (MQS) under a vertically differentiated duopoly. We generalize the model in Ronnen (1991) and Valletti (2000) by introducing asymmetry into the fixed cost of quality improvement and by explicitly taking into account the endogeneity of quality ordering. In the generalized model, we show that the results derived by Ronnen (1991) and Valletti (2000) are largely robust.     

Heterogeneous duopoly with isoelastic demand function

In this paper we analyze a duopolistic market with heterogeneous firms when the demand function is isoelastic (Puu, T., 1991. Chaos in duopoly pricing. Chaos, Solitons and Fractals 1, 573–581.). We consider the same heterogeneous firms of Zhang et al. (Zhang, J., Da, Q., Wang, Y., 2007. Analysis of nonlinear duopoly game with heterogeneous players. Economic Modelling 24, 138–148.) introducing a nonlinearity in the demand function instead of the cost function. Stability conditions of the Nash equilibrium and complex dynamics are studied. In particular we show two different routes to complicated dynamics: a cascade of flip bifurcations leading to periodic cycles (and chaos) and the Neimark-Sacker bifurcation which originates an attractive invariant closed curve. Comparisons with respect to the Puu model and the model of Zhang et al. are performed.     

Effect of credible quality investment with Bertrand and Cournot competition

We show how credible revelation and ability to commit to quality choice effect equilibrium qualities and welfare when product market is either Bertrand or Cournot competition. We show that results depend on the type of competition but not generally on the cost of quality function. We show that with Bertrand competition, the equilibrium qualities are lower with credible commitment. Competition is moderated and producer surplus is higher and consumer surplus lower. With Cournot competition, higher quality will be better but lower quality will be worse with credible commitment. Consumer surplus is always greater with credible commitment and if cost does not increase too quickly with quality, producer surplus will also increase. Thus credible commitment is a collusive device with Bertrand competition but it can improve social welfare with Cournot competition. Received: February 8, 2000; revised version: February 14, 2002 RID="*" ID="*" The idea of this paper originated in the weekly workshops of Mordecai Kurz at Stanford. I am forever in debted to Mordecai and fellow students – Luis Cabral, Peter DeMarzo, John Hillas, Michihiro Kandori, Steve Langois, Patrick McAllister, Steve Sharpe, Peter Streufert, Steve Turnbull and Gyu-Ho Wang – for their criticism and encouragement. I also benefited from comments from Yi-Heng Chen, Jin-Li Hu, Kala Krishna, Jinji Naoto, Thomas J. Prusa, and Shyh-Fang Ueng at various later stages of this work. Last but not least, I am grateful for the detailed comments of the referee.     

Forward trading and collusion in oligopoly

We consider an infinitely repeated oligopoly in which at each period firms not only serve the spot market by either competing in prices or quantities but also have the opportunity to trade forward contracts. Contrary to the pro-competitive results of finite-horizon models, we find that the possibility of forward trading allows firms to sustain collusive profits that otherwise would not be possible to achieve. The result holds both for price and quantity competition and follows because (collusive) contracting of future sales is more effective in deterring deviations from the collusive plan than inducing the previously identified pro-competitive effects.     

Kreps & Scheinkman with Product Differentiation

Kreps and Scheinkman (1983)’s celebrated result is that in a two-stage model of a market with homogeneous products in which firms noncooperatively pick capacities in the first stage and set prices in the second stage, the equilibrium outcome is that of a one-shot Cournot game. This note derives capacity best response functions for the first stage and extends the Kreps and Scheinkman result to the case of differentiated products.     

Do Antitrust Laws Facilitate Collusion? Experimental Evidence on Costly Communication in Duopolies*

Bertrand supergames with non‐binding communication are used to study price formation and stability of collusive agreements on experimental duopoly markets. The experimental design consists of three treatments with different costs of communication: zero‐cost, low‐cost and high‐cost. Prices are found to be significantly higher when communication is costly. Moreover, costly communication decreases the number of messages, but more importantly, it enhances the stability of collusive agreements. McCutcheon (1997) presents an interesting application to antitrust policy by letting the cost of communication symbolize the presence of an antitrust law that prohibits firms from discussing prices. Although our experimental results do not support the mechanism of McCutcheon's (1997) argument, the findings point in the direction of her prediction that antitrust laws might work in the interest of firms.     

International duopoly with overseas production and strategic trade policies

This paper examines the strategic export policies in a reciprocal market model of an international Cournot duopoly where two firms in domestic and foreign countries reciprocally supply their products to other countries through overseas production as well as export. It also considers the fact that the firms must incur export costs in addition to production costs. Thus, this paper shows, among others, that the effects of export policies on firms' output and export choices do not depend on the slopes of firms' reaction curves. It is also shown that firms' total outputs are independent of the export policies, and the optimal domestic and foreign export subsidies are zero (laissez-faire).     

How do advertised brands benefit from private labels? An application of rational expectations models

Private labels have traditionally been viewed as a threat to advertised brands. Contrary to traditional wisdom, this study uses a two-asset rational expectations model to show that advertised brands could benefit from private labels. While the manufacturer’s advertising creates product differentiation, the retailer’s synchronous pricing strategy further enhances the product differentiation and raises profits as well as the efficiency of price discounts for the advertised brand. In addition, the existence of private labels improves the advertising efficiency, especially for newly introduced brands. The economic role of private labels is not limited to taking a free ride on the manufacturer’s advertising efforts, and this role cannot be replaced by another advertised brand.