要旨：A spatial production model is developed for analyzing the American farming frontier. The basic model focuses on the decision problem of a farmer in the hinterland of a single point market. It is shown that positive production at the frontier requires some degree of local scale economies in production. The model is analyzed for the case of a logistic-type production function exhibiting these properties. In addition, it is shown that there exist stable relations between frontier production and production at all locations which are independent of market prices. The paper concludes with a derivation of the total market supply resulting from this individual decision model, and is illustrated by means of a numerical example.

要旨：The major four stages of the spatial-cycles are quantitatively examined, by use of the data extending over the past fifty years (for the period 1947-2000), for the two kinds of urban systems in Japan. The one is the spatial system of primary core cities, and the other is that of the Tokyo Metropolitan Area. The spatial-cycle hypothesis constructed by Klassen and the method of the Roxy-index analysis developed by the author are applied to our investigation. The results obtained illuminate rather clearly the recent trend of the revived agglomeration of the population in the core cities of large metropolitan areas, especially that towards the central part of the Tokyo Metropolitan Area. This would imply that the core city of the Tokyo Metropolitan Area will play an increasingly critical role in the urban policies of Japan, as compared with either its suburban area or the core cities of other metropolitan areas.

要旨：We study stability and instability of short-run and long-run equilibria of monopolistic competition with product differentiation. Since monopolistic competition is not either a game of complete information or of incomplete information, dynamic adjustment process of prices should exist in markets given the set of incumbent firms. Moreover, entry and exit of firms occur depending on the levels of individual profits. In the economies under investigation, the total income level of consumers determines whether the differentiated commodities are substitutes or complementarities. We show that there may exist unstable short-run equilibrium and long-run equilibrium. The reason is characterized by decreasing marginal cost and endogenous complementarities between differentiated commodities.

要旨：ハリウッドの映画製作におけるＶＦＸプロジェクトの責任者であるＶＦＸスーパーバイザーの週間コンタクト行動のデータを参加観察により収集し、デジタル・コンテンツ産業集積においてプロジェクトがどのようにコーディネートされているかについてコミュニケーションの側面から分析を行った。

要旨：The purpose of this paper is to discuss the efficient disposal system of industrial waste and the optimal policy to establish it. The economy of our model is composed by four organizations; dischargers, treatment firms, reclaiming firms, and the local governments. To begin with, discharges commission treatment firms to treat them. The treatment firms are imposed the industrial wastes tax by the local governments. The local governments can select either the strict monitoring policy or the subsidy policy for proper treating and can use tax revenues from the industrial waste tax. As the result of our analysis in this paper, we can derive the fact that the recycling rate under the strict monitoring policy is higher that the social optimal rate of recycle of the industrial waste if the local governments choice this policy and use the tax revenues to accomplish it. On the other hand, the social optimal recycling rate of them is established by the subsidy policy for the proper treating when the local governments choice this policy. In our analysis, we can derive some results. One of them is the fact that the recycling rate in the region whose government adopts the subsidy policy for the proper treating is higher than the optimal recycling rate in the region when the interregional transportation cost of industrial wastes is not high relatively. Another results is that it is possible to exist the policy combination of the strict monitoring policies as the equilibrium in spite of social non optimal combination if we take account of the interregional moving of the wastes.

要旨：We propose a simple framework within which taste heterogeneity is a determinant of the scale of production. We show: (i) when taste heterogeneity is small, mass production firms emerge; (ii) when taste heterogeneity is large, small-scale production firms emerge; and (iii) when the degree of taste heterogeneity is intermediate, the symmetric equilibrium is unstable, and mass production firms and small-scale production firms coexist. Furthermore, we extend it to a geographic framework and obtain a historical evolution of American marketing that is characterized by three phases: a geographically fragmented market with small-scale production; a geographically unified market with mass production; and a geographically unified but characteristically segmented market.

要旨：Cremer et al.(1997、Journal of Public Economics)のAll or nothingの公共財供給モデルを紹介し、これまでの拡張研究を通じて、同モデルの有効性を示す。

要旨：この論文は、近年日本において提案された都市雇用圏（金本・徳岡、2002）をベースに、都市規模に関する経済理論及び各種社会経済の統計データを応用して最適都市規模を実証したものである。その結果、2000年の都市雇用圏の最適規模は約1,800万人と推計された。そして、この最適都市規模の観点により、3,200万人を有する東京圏は明らかに過大であり、1,200万人の大阪圏や500万人の名古屋圏は過小であると結論付けた。

要旨：In this paper, we develop a two-country four-region model allowing for a core periphery pattern inside countries. We then examine how both the integration and the agglomeration process inside a given country affects the pattern of specialization and international trade. We also analyze how agglomeration processes interact from one country to the other and in particular how agglomeration forces in one country is affected by the spatial distribution of activity in the partner country. The main results of the analysis are the following: (i) agglomeration proves to be a source of comparative advantages in the industries featuring economies of scale on condition that this agglomeration process is driven by market forces; (ii) both integration and agglomeration in one country reduces the likelihood to observe agglomeration in the partner country.