考虑港口收费管制的进出口贸易竞争研究

考虑港口的收费管制因素,建立了进出口贸易竞争模型。该模型由一个出口国和两个进口国组成,且各国都拥有一个港口,位于出口国的两家公司均向两个进口国销售商品,并在各个进口国展开市场竞争（古诺竞争或伯川德竞争）,各贸易国的港口根据其是否存在价格管制确定港口收费。针对进出口公司的每种竞争模式,得到了不同的港口收费管制组合下各贸易国的港口收费、港口利润和社会福利,并将竞争均衡结果进行了比较。研究发现： （1）在进出口公司古诺竞争模式下,若三个贸易国的港口都无收费管制（有收费管制）且进出口产品的差异较大 （小）时,各贸易国的社会福利和港口利润均更高; （2）在进出口公司伯川德竞争模式下,若进出口产品的差异较大 （小）,则出口国的港口利润主要取决于港口收费 （贸易量）,而进口国恰好相反; （3）当进出口产品的差异较大 （小）时,进出口公司在古诺 （伯川德）竞争模式下各贸易国的社会福利、港口利润以及港口使用费都更高。     

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.     

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.     

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.      

WELFARE IN THE NASH EQUILIBRIUM IN EXPORT TAXES UNDER BERTRAND DUOPOLY

In the Eaton and Grossman Quarterly Journal of Economics, 101 (1986), pp. 383–406 model of export taxes under Bertrand duopoly, it is shown that welfare in the Nash equilibrium in export taxes is always higher than welfare under free trade for both countries.     

不对称R＆D活动下的市场绩效分析——基于有差异产品的寡头市场

为了研究在Stackelberg寡头竞争模型下企业在产品市场是否合作对市场绩效的影响,建立了寡头市场中面向R＆D工艺的两阶段博弈模型。采用逆向归纳法求出了产品市场合作与不合作两种情况下的古诺-均衡解。研究表明,从促进技术进步的角度来看,对于R＆D效率不太高的R＆D项目,产品市场合作策略优于产品市场竞争策略。从提高企业利润的角度来看,对于R＆D效率较高的R＆D项目,当产品差异不大时,产品市场合作策略优于产品市场竞争策略;当产品差异较大时,产品市场竞争策略优于产品市场合作策略。对于R＆D效率较低的R＆D项目,产品市场竞争策略优于产品市场合作策略。从提高消费者剩余以及改善社会福利的角度来看,对于R＆D效率较低的R＆D项目,产品市场竞争策略优于产品市场合作策略。     

Cournot and Bertrand Games

The author describes a series of matrix choice games illustrating monopoly, shared monopoly, Cournot, Bertrand, and Stackelberg behavior given either perfect complements or perfect substitutes. The games are created by using a spreadsheet to fill out a profit table given the choices of two players. One player selects the column, the other the row, and the table gives the profit of the row chooser. Because each player has a table, each thinks of him- or herself as the row chooser and the other as the column chooser. The games may be applied to international trade through the traditional Boeing v. Airbus story or, more currently, through foreign sales corporations. Addition of Bertrand competition allows discussion of price wars, and addition of perfect complements allows discussion of the proposed Microsoft breakup.     

Information Advantage in Cournot Oligopoly

Consider an oligopolistic industry where firms have access to the same technology but are asymmetrically informed about the environment. Even though it is commonplace to think that in this context superior information leads to higher profits, we find that under Cournot competition this is not generally the case: It holds when firms' technology exhibits constant returns to scale, but it does not necessarily hold otherwise. Journal of Economic Literature Classification Numbers: C72, D43, L13.     

Individual best response in the repeated Cournot model

We propose a particular style of punishments to support collusive behavior in an infinitely repeated Cournot oligopoly model for at least the same range of discount factors as Friedman’s trigger strategies. The punishment lasts for a finite number of periods and asymmetry is introduced in such a way that each punisher’s output is the individual best response.      

Exchange rates and bertrand oligopoly

The impact of exchange-rate changes on industrial prices seems ambiguous. Incomplete and even perverse pass-through has been observed: the import prices in the depreciating country decrease while those in the appreciating country increase. To explain these counterintuitive price reactions we consider a situation of international Bertrand competition: two firms, based in different countries, are selling in both countries simultaneously. The profit-maximizing duopolists set the prices for their products in each of the two markets which are segmented on the demand side. We then study the qualitative effect of an exogenous exchange-rate change on the Bertrand-Nash equilibrium. Under the strong assumption of linear demand and cost functions we have normal exchange-rate pass-through. However, allowing for more general cost structures in this simple static model enables us to show that the import prices in both countries might move in counterintuitive directions.     

中国传媒产业的战略趋势——基于中视传媒与分众传媒的比较分析

本文选择中视传媒和分众传媒作为典型个案进行对比分析,深入探讨在2008年奥运会前后,面临新媒体技术飞速发展带来的高度战略不确定性的特殊时期,中国传媒上市公司的现实作用与地位,分析它们能否从中小企业升级为行业领军者。这对于正在经历深度内部体制改革的中国传媒业来说,意味着整个产业能否实现从寡头垄断向垄断竞争的战略转变。     

Oligopolistic Competition and New Technology Adoption under Uncertainty

The paper examines the adoption of a new technology in oligopoly, where there is ex ante uncertainty about variable costs of the new technology. Each firm can either adopt the new process by bearing some up-front investment or may continue to use the old one, after which firms play a Cournot market game. If in equilibrium both technologies are employed, more uncertainty about the new technology increases (decreases) the number of innovating firms and decreases (increases) the product price if the up-front investment is large (small). Our model applies readily to vertical integration if integrated firms neither buy nor sell the intermediate good on the market. However, if buying and selling is allowed, the number of integrated firms is independent of input price uncertainty.