要旨：2005年8月、秋葉原とつくばを最短45分で繋ぐつくばエクスプレス(TX)が開通した。TX沿線地域の多くはそれまで長い間鉄道空白域であり、TXは首都圏最後の大規模鉄道プロジェクとしてその開発効果が注目されている。本研究では、TX開業前後10年間の沿線地域の公示地価に着目し，その間における地価の変動を分析する。まず、GISと空間内挿手法を用いてTX沿線地域における公示地価の変化を視覚化・抽出し、地価分布の変化について考察する。次に空間計量経済学・空間統計学・計量地理学、各々の考え方を用いて、地価データに内在する空間的な相関を考慮した様々な地価モデルを作成し、それらの結果を定量的に比較分析する。さらに、それらの結果をもとに、地域による開発効果の顕在化の相違を実証的に明らかにし、都市計画的な観点からこれを考察するとともに、資産価値法に基づく便益評価における留意点について議論する。

要旨：Classical discrete choice models are often used to depict a consumer's micro behavior of which brand to buy; however, they adopt an a priori assumption about a consumer's individual behavior that he or she demands at most unity. This assumption is sometimes unrealistic, especially when the goods analyzed are daily goods, such as food, because a consumer buys multiple units of multiple brands and different consumers demand different amounts. The purpose of this paper is to construct models that allow more flexible individual behaviors that are consistent with the results of discrete choice models. We formulate utility maximization problems that give demand functions equivalent to those from discrete choice models, explicitly taking into account the aggregation structure of consumers, and examine their characteristics from various aspects, such as the form of the utility function, elasticities, and measurement of welfare.

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.