要旨：This note proposes a three-country model of monopolistic competition that captures the role of time zones in the division of labor. The connectivity of business service sectors via communications networks (e.g., the Internet, satellite communications systems) is found to determine the structure of comparative advantage. That is, two countries with connected service sectors have a comparative advantage in the good that requires business services. It is also shown that the third unconnected country inevitably specializes in the good that does not require business services.

要旨：Constructing a two-country oligopolistic model where each oligopolist's production is subject to external economies of scale, this paper characterizes the trading equilibria, and explores trade patterns and gains from trade in each possible equilibrium. Whether a country exports the increasing returns good and gains from trade highly depends on the relative magnitude of increasing returns to the number of oligopolists, i.e., market power in the oligopolistic sector. It is carefully studied how these two fundamentals interactively determine the equilibrium trade pattern and the distribution of trade gains.

要旨：ファンと呼ばれる消費者が企業間の競争において持つ存在意義を空間競争モデルによって明示的に分析する。近い製品特性をもった製品同士が微妙に差別化された状況で価格競争をしのぎ合いながら、密集した財のバラエティを実現している状況がある。例えば、緑茶飲料などはごくわずかな差異を持った製品が数多く存在する。このような密集した多様性が競争から生み出される要因はファンと呼ばれる消費者にあると考えられる。本研究ではそれらの消費者に焦点を当てて、彼らが市場において果たす役割について分析する。具体的には、ファンの存在をホテリング線分上に明示的に導入した空間競争モデルを考え、企業数2 の2 段階空間競争モデルで、より近い立地で製品特性と価格の競争をランダムにおこなう均衡が得られることを示す。

要旨：This paper establishes the existence and efficiency of equilibrium in a local public goods economy with spatial structures by formalizing Hamilton's (1975 Urban Studies) elaboration of Tiebout's (1956 JPE) tale. We use a well-known equilibrium concept from Rothschild and Stiglitz (1976, QJE) in a market with asymmetric information, and show that Hamilton's zoning policy plays an essential role in proving existence and efficiency of equilibrium. We use an idealized large economy following Ellickson, Grodal, Scotchmer and Zame (1999, Econometrica) and Allouch, Conley and Wooders (2004). Our theorem is directly applicable to the existence and efficiency of a discrete approximation of mono-or multi-centric city equilibrium in urban economics with commuting time costs even if we allow existence of multiple qualities of (collective) residences, when externalities due to traffic congestion are not present.

要旨：This paper argues that currently advanced, aging economies experienced a qualitative change in the role of public education during the process of industrialization. In the early stages of the Industrial Revolution, public education was regarded as a duty that regulated child labor and thereby discouraged childbirth. As these economies developed and the population aged, younger generations came to view public education as a right, whereas older generations desirous of other public services became more politically influential. The eventual policy bias in favor of the elderly placed a heavier education burden on the young, inducing them to have fewer children. This vicious cycle between population aging and the undersupply of public education may have decelerated economic growth in the last few decades.

要旨：Using a model with a fixed cost of regional development, this paper considers how capital tax competition affects transfer and development policies in the presence of regional income disparity. In each country, development policies determine the number of rich (poor) regions that (do not) engage in production activities while transfer policies redistribute income between rich and poor regions. It is shown that the mix of transfer and development policies, as well as the overall expenditure level, is inefficient under tax competition. Since capital tax distortion causes competing governments to overvalue the benefit of regional development, too much tax revenue is spent on development policies and too little on transfer policies. As a result, development policies are used as a means of regional redistribution even if transfer policies are efficient instruments for this purpose.

要旨：We analyze the impact of globalization on individual gains from trade in a general equilibrium model of monopolistic competition featuring income heterogeneity between and within countries. We disentangle two key channels through which trade affects welfare: product diversity and pro-competitive effects. We then show that, although trade always reduces the price-wage ratios in both countries, its impact on variety depends on their relative position in the world income distribution: the choice set in the low income country always expands, while that in the high income country may shrink. When the latter occurs, the richer consumers in the high income country may lose from trade because the relative importance of product diversity versus purchasing power increases with income. To illustrate the quantitative effects, we calibrate the model on the U.S. income distribution and show that U.S. trade with countries of similar GDP per capita makes all agents in both countries better off; whereas trade with larger countries having lower GDP per capita may adversely affect the richest 12-20% of the U.S. population.

【応用ミクロ経済学・産業経済学ワークショップと共催】 要旨：To alleviate congestion and facilitate Asia-Pacific trade the federal and western provincial governments have launched several major transportation infrastructure investments. This paper addresses some public policy issues regarding infrastructure investments of this type. Does the private sector have incentives to make efficient investments and to impose efficient congestion charges? What about local governments? Are subsidies warranted either for investments or for ongoing operations and maintenance of infrastructure? Should governments pursue strategic trade objectives? Do existing institutions, governance structures and regulations facilitate appropriate decisions? Some dangers of making wrong investment decisions are identified.

【応用ミクロ経済学・産業経済学ワークショップと共催】 要旨：We analyze agents' strategic interaction of investment in security and bilateral partnership among them. Each agent confronts with a risk of suffering damage from troubles and disasters such as natural disaster and terrorism. To deal with them, agents have a choice to have investment in pre-disaster phase and partnerships of post-disaster recovery activity. We examine efficient and stable investment in security and partnership network in the game and tension between efficiency and stability. We also compare payoffs of stable networks if multiple networks are stable.