ON THE SUSTAINABILITY OF COLLUSION IN A DIFFERENTIATED OLIGOPOLY WITH A CARTEL AND A FRINGE

We discuss the effects of the existence of non‐colluding (fringe) firms on cartel sustainability. We obtain, using trigger strategies, that with product differentiation collusion is always more easily sustained when firms compete in prices than when firms compete in quantities. This is true basically because (i) price competition is more intense than quantity competition, and (ii) fringe firms exacerbate the fact that cartel firms have more incentives to deviate from the agreement under quantity competition. This result reverses previous findings where, in the absence of fringe firms, product differentiation plays a crucial role in determining the effectiveness of price or quantity competition in sustaining collusion.     

Product differentiation,price discrimination and collusion

The existing literature which analyses the relationship between the product differentiation degree and the sustainability of a collusive agreement on price assumes that firms cannot price discriminate, and concludes that there is a negative relationship between the product differentiation degree and the critical discount factor. This paper, in contrast, assumes that firms are able to price discriminate. Within the Hotelling framework, three different collusive schemes are studied: perfect collusion on discriminatory prices; perfect collusion on a uniform price; collusion not to discriminate. We obtain that the critical discount factor of the first and the third collusive scheme does not depend on the product differentiation degree, while the critical discount factor of the second collusive scheme depends positively on the product differentiation degree. Moreover, we show that imperfect collusion is more difficult to sustain than perfect collusion.     

Endogenous rationing,price dispersion and collusion in capacity constrained supergames

This paper examines the feasibility of collusion in capacity constrained duopoly supergames. In each period firms simultaneously set a price–quantity pair specifying the price for the period and the maximum quantity the firm is willing to sell at this price. Under price–quantity competition firms are able to ration their output below capacity. For a wide range of capacity pairs, the equilibrium path providing the smaller firm with its highest stationary perfect equilibrium payoff requires that it undercut its rival’s price and ration demand. Furthermore, for some capacities and discount factors supporting security level punishments, price shading and rationing arise everywhere on the set of stationary perfect equilibrium paths yielding (constrained) Pareto optimal payoffs. That is, price shading may not only be consistent with optimal collusion, it may be a requirement of optimal collusion.     

Price collusion with free entry: the parasitic competition

The market equilibrium that is generated in the presence of both price collusion and free entry is analyzed taking under consideration the case of a homogeneous product and the case of differentiated products. The outcomes of this market regime are compared with those of other regimes, including competition (or monopolistic competition), monopoly, fixed price with collusive entry limitation. Some welfare implications of the market regime of price collusion with free entry are examined, with respect to the maximum social welfare allocation and the allocations of other market regimes, so to highlight the inefficiency of price collusion with free entry. The number of producers results to be the maximum number of firms that can produce without incurring into losses. Therefore, social distress is caused by a displacement from the price collusion equilibrium with free entry. Its defence can thus be considered in reference to the desirability of social goals that are in contradiction with economic efficiency.     

电信产业默契合谋的存在性与稳定性分析

合谋是产业组织理论研究的重要问题之一,它易出现于寡头垄断行业中。合谋的出现会降低消费者剩余,对整个社会福利造成损失,因此应当尽量去除。电信产业是一个典型的寡头垄断产业,电信运营商之间具有很强的相互依赖性,易出现合谋,特别是默契合谋。所谓默契合谋是指寡头垄断厂商以一种纯粹“非合作”的方式进行的合作。本文首先应用古诺模型对电信产业默契合谋的存在性进行理论分析,并举出实例予以佐证。在此基础上,从理论上进一步证明了电信产业默契合谋具有不稳定性,指出运营商之间的合谋是一个“囚徒困境”。进而应用冷酷策略,研究了电信产业默契合谋维持的激励条件,并从成本对称性、市场信息透明度、产品差异性、卖方集中度和技术进步程度等方面分析了影响电信产业默契合谋的相关因素。并指出现实中,默契合谋和价格竞争往往是交替出现的。     

Can product differentiation mitigate conflicts of interest between principal stakeholders? A cournot-bertrand comparison

This paper aims to investigate the impact of product differentiation on the extent of conflict of interest between principal stakeholders (shareholders, employees, and consumers), which is one of the most important concerns of stakeholder-oriented corporate governance. We consider a differentiated duopoly competing either in price or quantity after the wages of employees are negotiated with a labor union. We find that price competition and quantity competition have drastically different implications on whether product differentiation mitigates stakeholders' conflicts. Specifically, product differentiation can mitigate stakeholders' conflicts when firms compete in price, but not when they compete in quantity. Therefore, the product differentiation effect in mitigating stakeholders' conflicts differs across markets characterized by price competition versus quantity competition.     

Biased managers as strategic commitment: The relative profit approach

This paper analyzes a duopolistic model wherein each firm׳s owner can hire a biased manager for strategic reasons. We focus on the situation wherein each firm׳s owner evaluates the performance of her/his manager on the basis of her/his relative profit, which is equal to the weighted sum of her/his absolute profit and the absolute profit of her/his opponent firm. We show that in both price-setting and quantity-setting competitions, the owners of the two private firms employ aggressive managers rather than absolute profit maximizing managers regardless of the degree of importance of each firm׳s relative performance. Furthermore, in both the price competition and the quantity competition, as the degree of importance of each firm׳s relative performance increases, we show that the firms׳ owners tend to hire more aggressive managers when the degree of importance of each firm׳s relative performance is sufficiently low, whereas in both the price competition and the quantity competition, the firms׳ owners tend to hire less aggressive managers otherwise. Thus, in both the price competition and the quantity competition, the type of each firm׳s manager is not monotone with respect to the degree of each firm׳s relative performance. Thus, in both the price competition and the quantity competition, we find that the change in the optimal type of manager hired by each firm is non-monotone against the change of competitiveness in the market with the increase in the degree of importance of each firm׳s relative performance.     

Market collusion and the politics of protection

This paper investigates the relationship between trade and competition policy within a model where market collusion and protectionist lobbying are themselves related. Collusion and lobbying are modeled as joint products of the same collective effort of firms. In equilibrium, firms cannot achieve greater cooperation in one dimension without reducing it in the other. A trade agreement that limits the effectiveness of lobbying may cause firms to increase market collusion, thereby increasing the domestic price. Thus, international trade agreements may run counter to the goals of competition policy. On the other side, a more restrictive competition policy is shown to either reduce the domestic price or reduce import protection. Thus, competition policy tends to promote trade policy goals. The reason is that restrictive competition policy undermines collusion at the source—it decreases the per-firm benefit to collusion relative to the gains from deviating—reducing firm cooperation in both dimensions.     

差异化产品价格战的产生与扩散机制分析

本文基于消费者的"0-1"购买特征和产品的纵向差异化特征,建立了一个新的价格战模型。通过应用数学证明和数值模拟的方法发现:(1)合谋体系、背叛体系以及价格战体系的均衡结果均与需求冲击无关;(2)差异化产品厂商的背叛动机以及产品链条的合谋稳定性也与需求冲击无关;(3)产品的差异化程度是影响合谋稳定性的重要因素,差异化程度越大,合谋越稳定;(4)合谋集团对背叛厂商的惩罚策略存在着"误伤效应",这种效应在一定条件下能够自我抑制,表现为产品链条上的价格战和合谋共存,在其他条件下,这种效应不能自我抑制,价格战一旦发动就会迅速扩散到整个产品链条。     

On the role of network externalities in strategic delegation contracts with an industry-wide union

This article analyses the role of network externalities in managerial delegation contracts for differentiated products when the marginal product costs (the wage) are set by an industry-wide union. The results show that, in both Bertrand and Cournot equilibria, each owner offers a profit-oriented incentive scheme to his or her managers by penalizing sales maximization, irrespective of the strength of the network externalities. In the presence of weak network externalities and low product differentiation, firms can obtain higher profits in the equilibrium under Cournot-type quantity competition compared with that under Bertrand-type price competition. Furthermore, the wage chosen by the union is higher in the Cournot than in the Bertrand equilibrium. In the Cournot equilibrium, the wage increases with the strength of the network externalities. However, in the Bertrand equilibrium, there exists a threshold level of the degree of product differentiation.     

Collusion in Differentiated Duopolies with Quadratic Costs

The analysis of collusion in infinitely repeated duopoly games has generally assumed that marginal cost is constant, but this note uses quadratic costs (linear marginal costs) to compare the sustainability of collusion under Bertrand and Cournot duopoly with differentiated products. It is shown that when marginal costs are sufficiently increasing in output, then it is always easier to sustain collusion under Cournot duopoly than under Bertrand duopoly for any degree of product substitutability.     

Costly horizontal differentiation

We study the effect of quadratic differentiation costs in the Hotelling model of endogenous product differentiation. The equilibrium location choices are found to depend on the magnitude of the differentiation costs (relatively to the transportation costs supported by consumers). When the differentiation costs are low, there is maximum differentiation. When they are high, there is partial differentiation, with a degree of differentiation that decreases with the differentiation costs. In any case, the socially optimal degree of differentiation is always lower than the equilibrium level. We also study the case of collusion between firms. If firms can combine locations but not prices, they locate asymmetrically when differentiation costs are high and choose maximum differentiation when they are low. When collusion extends to price setting, there is partial differentiation.     

垂直差异化与合谋稳定性关系分析

市场行为中的默契合谋能使企业获得超额利润,现存的关于生产同质品和差异化产品的经验性研究经常能发现默契合谋的证据.在现实经济的默契合谋行为中,不同的成本结构适用于不同的经济环境或者不同的行业、产业分析,也直接影响着合谋和背离合谋所得的利润,对合谋稳定性有着重要的影响.在垂直差异化的不同成本(固定成本、可变成本)结构下,企业参与竞争的不同竞争类型(古诺竞争和伯川德竞争)对合谋稳定性的影响也是有差异的.     

标准专利许可中可变价格的社会福利效应:基于产品差异化的视角

技术标准在产品生产过程中的使用越来越广泛,标准专利许可定价形式问题关系到技术标准所有者和产品生产者的收益,有待拓展研究。通过构建古诺竞争模型,从产品差异化角度对标准专利许可中可变价格形式的社会福利效应进行分析,得到的主要结论为:当产品市场达到均衡,且标准专利许可采用的价格形式是可变价格时,社会总福利随着产品差异化程度的提高而增加,随着差异化产品市场中标准专利使用者数量的增加而增加,随着可变价格中可变费用比率的提高而降低;均衡产量随着产品差异化程度的提高而增大,随着可变价格中可变费用比率的提高而降低;均衡价格与产品差异化程度呈现出倒“U”型关系,临界点为特定的市场规模;标准专利使用者的均衡利润随着产品差异化程度的提高而增大。由此可见,标准专利许可的可变费用比率下降有利于激励技术标准使用者生产更多的差异化产品,提升社会总福利。     

Price vs quantity in a duopoly supergame with Nash punishments

We examine the endogenous choice between price and quantity behaviour in a duopoly supergame with product differentiation. We find that (i) if cartel profits are evenly split between firms, then only symmetric equilibria s obtained; (i) if instead the additional profits available through collusion are split according to the Nash bargaining solution, there are parameter regions where all subgame perfect equilibria are asymmetric, with firms colluding in price–quantity supergames.     

Unionized labor market and licensing by a monopolist

We show that a monopolistic final goods producer may find it profitable to create competition by licensing its technology if the input market is imperfectly competitive. With a centralized union, we show that licensing by a monopolist is profitable under both uniform and discriminatory wage settings by the union. However, the incentive for licensing is higher under the former situation. We also show that licensing by the monopolist is profitable under both quantity and price competition, and the incentive for licensing is higher under price competition than under quantity competition. Our qualitative results hold even with decentralized unions.      

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。     

Collusive behaviour under cost asymmetries when firms compete in supply functions

This paper investigates the effect of cost heterogeneity in cartel formation and its sustainability over time when firms compete in supply functions under uncertainty. We find that cartel formation and collusion sustainability are hindered as cost differences increase. Efficiency losses caused by collusive behaviour are shown to decrease as asymmetry increases and, therefore, welfare losses also decrease. We compare our results with those obtained under Cournot and Bertrand competition.     

The empirical content of Cournot competition

We consider the testable implications of the Cournot model of market competition. Our approach is nonparametric in the sense that we abstain from imposing any functional specification on market demand and firm cost functions. We derive necessary and sufficient conditions for (reduced form) equilibrium market price and quantity functions to be consistent with the Cournot model. In addition, we present identification results for the corresponding inverse market demand function and the firm cost functions. Finally, we use our approach to derive testable restrictions for the models of perfect competition, collusion and conjectural variations. This identifies the conditions under which these different models are empirically distinguishable from the Cournot model. We also investigate empirical issues (measurement error and omitted variables) related to bringing our testable restrictions to data.     

企业差异化战略对价格和质量竞争博弈均衡解的影响研究

消费者在购买商品时不仅考虑商品价格而且还要考虑商品质量水平的需求市场,如果存在两寡头企业提供某商品,必然会导致价格和质量的竞争博弈。本文研究表明:为了达到纳什均衡状态,两企业必须采取一定的差异化策略。而且在均衡状态下,如果市场是价格敏感市场,企业的差异化程度越高,对企业和消费者都越有利;如果市场是质量敏感市场,当敏感程度相对很低时,企业的差异化程度越高,对企业和消费者也都越有利;当敏感程度一般时企业可选择适当的差异化程度使得企业和消费者同时达到最大的均衡利润;但当敏感度非常高,企业差异化程度越高对企业的均衡利润越大,可对消费者的均衡利润却越小。