International Trade and Trade Policy under Imperfect Competition

本研究旨在重建国际贸易理论与贸易政策，并纳入不完全竞争与规模报酬可变的要素。关于这一主题已经有大量的文献，但其中大多数是在部分均衡分析的框架下发展起来的，并且倾向于得出关于贸易政策的不可知论结论，因为“在不完全竞争下任何事情都可能发生”。我尽可能使用一般均衡模型进行调查，并得出明确而明确的结论。我的研究结果可以总结如下。首先，我建立了一个不完全竞争和规模收益可变条件下的国际贸易一般均衡模型，从而扩展和重新检验了(a)李嘉图-穆勒或赫克舍尔=奥林的国际专业化理论和(b)格雷厄姆-埃尔的保护贸易理论。其次，构建了工会在城市工业部门行使垄断权力的开放二元经济模型，对Manoilesco=Hagen或Harris=Todaro的工业保护理论进行批判性反思。再次，运用部分均衡分析对国际销售竞争、技术赶超、产业内贸易等新问题进行了假设和检验。第四，为准备未来的发展，我构建了一个不完全竞争经济体的宏观经济模型，并将传统的最优政策理论扩展到两国框架。

This study aims to reconstruct the theory of international trade and trade policy incorporating elements of imperfect competition and variable returns to scale. There is already a vast literature on this subject but most of them is developed in the framework of patial equilibrium analysis and tend to produce agnostic conclusions about trade policy since "anything can happen under imperfect competition." I endeavored to carry out my investigation using general equilibrium models whenever possible and to derive clear and definitive conclusions. The results of my research may be summarized as follows.First, I developed a general equilibrium model of international trade under imperfect competition and variable returns to scale thereby extending and reexaming (a) the Ricardo-Mill or Heckscher=Ohlin theory of international specialization and (b) the Graham-Ethier theory of protective trade. Secondly, I constracted a model of open dualistic economy where labor union exerts monopoly power in the urban industrial sector to critically reconsider the Manoilesco=Hagen, or Harris=Todaro theory of industrial protection. Thirdly, I also employed partial equilibrium analysis to posit and examine the new problems, e.g., international sales competition, technological overtaking and intra-industry trade. Fourthly, in preparation for future developement, I constructed a macroeconomic model of imperfectly competitive economies and extended the conventional theory of optimal policy to a two-country framework.