【作者】 吴韧强；

【导师】 刘海云；

【作者基本信息】 华中科技大学 ， 西方经济学， 2007， 博士

【摘要】 本论文试图从政治经济学的角度,对国际贸易政策领域内,新古典贸易理论所无法解释的现象作出相关的经济学理论分析。由于,新古典贸易理论假设社会福利最大化为一国政府的目标函数,因此,在这样的假设前提下,自由贸易,在普遍意义上,便是一国所应遵循的最优贸易政策。然而,在现实中,国际贸易政策却并未像新古典贸易理论中所描述的如此单调,事实上,各国的贸易政策均与完全自由开放保持着偏差。随着日益扩大的全球贸易,贸易保护主意逐步抬头,并且国家对于国内产业的保护力度各不相同,保护力度在产业链上形成了阶梯安排;政府以补贴或出口退税等方式刺激出口,同时却对某些产业的出口加以限制。为了对不同的贸易政策走向提出理论上的经济学解释,本论文以Grossman与Helpman(1994)所构建的“保护待售”(Protection for Sale,缩写PFS)模型为基础,以利益集团对贸易政策的影响为切入点,以博弈论的方法,沿着从小国到大国,完全竞争到垄断竞争,非合作博弈到合作博弈的顺序,数理化地描述了,在利益集团游说下,一国执行贸易政策的政治过程,以及均衡贸易政策所体现的各种特征。本论文的分析方法均建立在利益集团利用政治捐献,通过政治途径,影响一国贸易政策的假设上。以此为前提,本论文首先从完全竞争情况下的小国情形入手,在PFS模型的基础上,嵌入了中间产品产业,比较最终商品与中间产品的均衡保护率,从政治经济学的视角,考察关税结构是否遵从,如“有效保护率”理论所提倡的,由上游至下游逐级递增的梯形结构。通过比较,本论文发现,关税结构并非时刻遵循“有效保护率”所倡导的梯形模式,梯形的关税结构只是大多数情况下均衡关税的一种表现形式,在少数情况下,由于上下游产业利益集团的实力悬殊,均衡关税设置可能表现为反向的逐级递减形式,当各最终商品厂商利益集团之间存在“搭便车”现象时,关税结构将在一段时间内出现不稳定的多种形式。其次,本论文通过诠释、拓展G-H贸易战模型,探讨了在完全竞争市场下,大国之间的内生贸易政策均衡安排以及贸易战规模。模型结论表明,大国之间的贸易政策存在“最优进(出)口关税”的非合作博弈纳什均衡;利益集团的出现将使政府在“最优关税”的基础之上,调整贸易政策,重新分配产业间的保护力度;大国之间利益集团的相对经济实力以及政府对政治捐献的相对关注程度,将影响贸易战的规模水平,在多数情况下,贸易战升级的原因应归于进口国国内政治经济环境所发生的改变。一国进口关税的提高将引致另一国出口补贴的增加,而一国的出口补贴反而有助于稳定另一国的进口关税。再次,由于PFS模型与G-H贸易战模型与现实情况存在一定差距,本论文依据Pao-Li Chang的研究方法,将完全竞争市场修正为垄断竞争,并将模型细分为小国与大国情形。本论文将垄断竞争引入PFS模型,研究了小国情形下,一国的进口保护政策所体现的特征。结论表明,在垄断竞争前提下,小国将存在“最优进口保护率”,无论是完全竞争市场还是垄断竞争条件,利益集团的出现均推涨了国内的贸易保护主义情绪,同时非利益集团的产业保护力度将有所降低,国家的保护力度始终取决于该国产品的相对初始竞争力与产品的差异化程度。然后,本论文将垄断竞争与G-H贸易战模型相结合,分析了大国之间,开展产业内贸易时,进出口政策并存的国际贸易政策。模型分析结论认为,与完全竞争市场相似,大国之间依然存在“最优进出口关税”,利益集团的产生将促使政府调整进出口政策,以利于利益集团的福利提高;并且,政府偏向于将优势产品集中于本国消费,对差异化程度较高的产品实行高水平的进出口壁垒;同时,利益集团的介入将引发两国之间的贸易战,政府对于政治捐献的偏好增加、产品竞争力的增强将单方面地提升贸易战规模,而产品差异化的扩大将带动贸易战的全面升级。最后,本论文研究了在垄断竞争情况下,利益集团对贸易谈判所带来的影响。本论文的结论表明,与贸易战不同,贸易谈判下的均衡进出口政策将不存在“最优进出口关税”,取而代之的则是类似于“最优进出口补贴”的政策安排。利益集团的出现,将改变政府在谈判桌前的态度,国内存在利益集团的政府,其态度将更为强硬。同时,竞争力较强的产业将借助贸易谈判扩大其在全球的产品销售量,产品差异化程度的提高将使双方政府更大程度地开放市场,提高出口支持力度,以维持双方贸易量。更多还原

【Abstract】 This dissertation gives canonical interpretaitons for some already existent phenomena in the international trade policy field Neo-Classical trade theory cannot comprehend. Neo-Classical trade theory proposes the hypothesis that the target utility of a government is no different with that of consumers, the trade policy set by the government is to maximize the welfare of the whole country, so under such condition, free trade policy is almost the best choice for a country. However, in the reality, the true international trade policy is not as monotony as what Neo-Classical trade theory describes. The trade policis exerted by conutries are seldom kept to be free. With the expanding scale of the international trade amount in the globe, trade protectionism is revivaling again. Moreover, different protective degree is allocated to different industry, and the protection power distributed in the industry chain forms a ladder hiberarchy. A government could stimulate the export by export subsidies or export tax rebation in one hand, in the onther hand practise measures on certain products to limit its export. Therefore, to give explanations for the various international trade policies, this dissertation analyzes the political process that interest groups access to the trade policy through the government by using game theory based on the "Protection for Sale" model, and studies the characters of the final equilibrious trade policy, keeping the order that from small country to large country, perfect competition to monopolistic competition, and non-cooperative game to cooperative game.The method this dissertation adopted is based on the hypothesis that interest groups are able to change the trade policy by political contribution. Under such premise, at first, this dissertation begins with a small country under perfect competition, inserts a intermediate-good industry into the PFS model, then, make a comparison between the protection rates on the intermediate good and final good to discover whether the tariff structure obeys what ERP theory predicts. A conclusion shows that, tariff structure is endogenous in the political economics system, of which the pattern is determined by the organization of interest groups representing industries and the differentiation between final goods industries. In most cases, the tariff structue presents an echelon form. But in some extreme cases, the power of upstream industry is much stronger than that of downstream, which makes the tariff structure reverse. When the "free riders" exist in the final good industries, the tariff structure will fluctuate in an interval.Secondly, this dissertation analyzes the international trade policies executed by two large countries under perfect competition, based on the G-H Trade War Model. The conclusion drawn from the model shows that, there exists a non-cooperative Nash Equilibrium as a optimal import and export tariff between two large countries; the interest groups will lobby the government to adopt a more favorable trade policy to substitute the optimal tariff, by using political contribution; the power of the interest groups and the weight government place on the political contribution will determine the level of trade wars; in most case, the upgrade of trade wars can be attributed to the change taken place in the political and economic environments in the importer country. Furtheremore, this dissertation discovers that one country’s augment of its import tariff will drive the other’s increase of subsidy, in turn; the subsidy of one country will restrain the protection rate effectly of the other.Thirdly, because of the defacts of PFS model and G-H trade wars model, this dissertation changes the perfect competiton market in PFS and G-H trade wars models into monopolistic competiton situation, following the research approach by Pao-Li Chang, making a deep classification of small and large country. Introducing monopolistic competiton to PFS model, this dissertation studies the characteristics of import protection in a small contry. Conclusions shows that, even in a small country, an "optimal tarde protection" will be adopted, as long as a monopolistic competiton market exists; interest groups bring the redistribution of the protection among industries, the weight that the government places on aggregate welfare determines the pattern of the redistribution; the government offers protection generally with a consistent attitude, the protection rate for an industry is an increasing function of its relative market share and the degree of its production differentiation.Fourthly, by combining G-H trdae war model with monopolistic competiton, this dissertation studies the endogeous trade policy combination between two large countries and the scale of trade wars. The conclusion drawn from shows that, there also exists an "optimal import and export tariff set" in those two countries, the countries will make an adjustment for the preference of Interest Groups, based on the optimal tariff; the governments are intended to enclose the products of advantage in the domestic to consume, and set higher import and export tariffs for the products of higher differentiation degree; Interest Groups contribute to the occurrence of trade wars between those two countries, the increase of the weight the government put on the political contribution and the competition power of products will drive up trade wars unilaterally, the enlargement of the products differentiation will intensify trade wars generally.Finally, this dissertation sudies the trade policy as the outcome of trade negotiation at the existence of interest group.What differs in the condition of trade negotiation from the conclusions under trade wars is that there exist an "optimal export and import subsidy" instead of an "optimal tariff set". Interest groups will change the attitude of the negotiator tougher. The products with comparible advantage will expand their globel market share with the help of trade negotiation. The increase in the differentiation degree of products will impel the government to exert the trade policy which is helpful to maintain the trade flow between coutries.更多还原