Possibilities of welfare improvement by policy coordination under tax competition

项目取得的成果如下：第一，考虑了区域间收入转移的福利效应。结果表明，在Heckscher-Ohlin(Ho)模型下，如果各国私人部门和公共部门的相对生产率差异相同，柴田-沃尔中立性定理是成立的。其次，研究表明，在国际混合寡头垄断下，公共企业私有化的福利效应可能取决于税收原则。我们发现，在包括一家外国私营企业的混合寡头垄断中，当政府战略性地设定基于目的地的商品税时，私有化会减少福利。然而，除了商品税，如果政府将进口关税作为一种战略手段，私有化还会增加福利。我们还发现，私有化的福利效应可能会因国内外私营企业的数量而有所不同。第三，我们考虑了税收竞争下的资源分配问题，即政府提供公共服务，以减少私人生产活动产生的公共不良。研究结果表明，为了实现资本的有效配置，来源地资本税和居住地资本税都是必要的，如果政府战略性地设置来源地资本税，公共部门成本的降低可能会降低公共部门的福利。我们将分局情况下的权力下放程度与统一局情况下的程度进行比较。我们发现，当只有一个地方政府可以进行游说时，统一的局会带来更高的分权和更小的中央政府规模。然而，在两个地方政府的游说下，通过分开局来加强权力下放。

The results obtained by the projects are as follows :First, welfare effects of interregional income transfer are considered. It is shown that the Shibata-Warr neutrality theorem is held under the Heckscher-Ohlin (HO) model if the difference in relative productivity between private and public sector are the same among countries. Furthermore, it is also shown that the second neutrality theorem due to Shibata is valid under the HO model.Second, the research shows that under international mixed oligopoly, welfare effects of privatisation of the public firm may depend on tax principles. We find that in a mixed oligopoly including one foreign private firm, the privatisation reduces welfare when the government strategically sets the destination based commodity tax. However, in addition to the commodity tax, if the government uses an import tariff as a strategic device, the privatisation increases the welfare. We also show that the welfare effects of privatisation can vary depending on the number of domestic and foreign private firms.Third, we consider the resource allocation under the tax competition in which governments supply the public service to reduce the public bads generating by the private production activities. It is shown that both origin and residence based capital taxes are needed to achieve efficient allocation of capital, and that the welfare may be reduced by the cost reduction of the public sector if the government strategically sets source based capital tax.Finally, we investigate the implication of separation of decision-making structure in the context of decentralization. We compare the extent of decentralization in the separated bureaus case with the extent in the unified bureaus case. We show that unifying bureaus brings higher decentralization and smaller size of central government when only one local government can lobby. However, decentralization is enhanced by separating bureaus under lobbying by both local governments.