An Analysis of the Effect on Welfare and Growth of Domestic Market Structure and Trade Policy

本研究课题是关于一国的市场组织、市场规则、市场法律对国际贸易和资本形成的各种影响的研究。这些影响已经分析了理论和实证方法。通过研究，大量的论文（21篇英文论文和6篇日文论文）主要发表在国际学术期刊上。（1）在具有可贸易品的上游市场和不可贸易服务的下游市场的垂直链国际贸易模式中，抑制下游市场的竞争会产生类似于征收关税的效果。此外，这一政策的影响实际上相当于关税政策的影响。(2)在网络外部性出现与新产品的推出，一个新的公司可能会以低于其边际成本的价格出售。这一结果应用于国际贸易，首次对政策文献中所谓的边际成本倾销给出了严肃的理论解释。(3)国内市场的竞争在很大程度上受到一国国内市场规则和法律的影响，这些规则和法律对该国的资本形成产生重大影响。特别是，这些研究揭示了从我称之为市场质量的观点分析市场机制的重要性，这可能为微观经济学提供全新的理论基础。

This four-year research project is on various effects on international trade and capital formation of a country's market organization, rules, and laws on markets. Those effects have been analyzed by both theoretical and empirical methods. Through the research, a large number of papers (21 English and 6 Japanese language papers) has been published mainly in international academic journals.The main findings of the research are as follows : (1) In a vertical-chain model of international trade that is equipped with an upstream market for tradables and a downstream market for non-tradable services, suppression of competition in the downstream market can create an effect similar to the imposition of a tariff. Moreover, the impact of that policy can be practically equivalent to that of a tariff policy. (2) In the presence of network externalities that appear in association with the introduction of a new product, a new firm may sell at a price below its marginal cost. This result, applied to international trade, gives the first serious theoretical explanation to what is called marginal cost dumping in the policy literature. (3) Competition in a domestic market is crucially affected by a country's domestic rules and laws on market, which significantly influence capital formation in that country.A message from these studies is that rules and laws on markets have significant impacts on the function of a market, either international or domestic. In particular, the studies have revealed the importance of an analysis of market mechanism from the viewpoint of what I call market quality, which may provide a totally new theoretical foundation for microeconomics.