要旨：We extend the model of Haufler and Wooton (1996) and construct a model with three countries in which a firm selects its location. A firm can select a location country from two countries, while in the third country, there is a market for the firm and are competitive rival firms. Then, the effect of the third country's market induces the firm to locate at a closer country from the third country. On the other hand, the effect of the existence of rival firms makes the firm to locate at a further country from the third country. With this framework, we study the location behavior of the firm, and consequences of tax competition between two countries and two countries' trade union.

要旨：This paper empirically tests the relationship among wage, market potential and interregional migration using structural estimation method in the framework of economic geography. We investigate migration of manufacturing workers between 47 Japanese prefectures. As a result we find that nominal wage is positively correlated with market potential and higher real wage prefecture attracts workers.

要旨：This paper examines the effect of port competition between two ports applying a game theoretical approach. We constructed a conceptual non-cooperative game theoretical model and this study intends to empirically apply the model to a competition case between the port of Busan and the port of Kobe. The results show that Japanese government decided conversely on pricing and the timing of capacity expansion, which explains why the Kobe port has resulted in deteriorating cargo throughput over the times.

要旨：Using the original survey data conducted to small and medium-sized firms in Zhongguancun Science Park (ZSP), we examine the effects of R&D cooperation on firms' intensity of R&D activities, with particular attention to type and proximity to partners like large sized firm, other small and medium-sized firm, and university and research institute. We found that direct effects to enhance employment R&D intensity of ZSP small firms from research cooperation with small and medium-sized firms, and university and research institute that are located nearby. Our results also suggest that indirect effects of research cooperation such that cooperation with nearby large firms and that with far-off small and medium-sized firms enhance further R&D of ZSP small firms when such cooperation yields commercial success.

要旨：This paper describes how differences in costs between downstream firms affect their relative performance in a Hotelling-type location model. I consider three aspects of production costs in discussing the effect of cost advantage on firm performance: (i) costs to differentiate their products, (ii) efficiencies of production, and (iii) endogenously determined input procurement conditions. I show that a less efficient firm can be the market leader if the per-unit production cost of each firm depends on its location (costs to differentiate their products exist) and if the firms procure inputs from outside suppliers. That is, the profit of a less efficient firm can be larger than that of a more efficient firm. In equilibrium, the less efficient firm locates closer to the center than the efficient firm. This equilibrium outcome is quite different from that in which the efficiency difference is given exogenously. Moreover, I investigate how a change of cost structures affects the profits of firms. I show that improving the procurement conditions of a firm does not always increase its profit, whereas improving its production efficiency always does.

要旨：By adding housing congestion to the model of Fujita and Thisse [Does geographical agglomeration foster economic growth? And who gains and who loses from it? Japanese Economic Review 54 (2003), 121-145], we study interactions among growth, agglomeration, and urban congestion. However, unlike Fujita and Thisse (2003), we formulate the model as a one-shot game and take an evolutionary game-theoretic approach for stability analysis. Our approach is simple and enables us to analyze stability of nonstationary equilibria. We show that if both expenditure share for housing and transport cost are small, a stable steady-state equilibrium does not exist. Moreover, in such a case, we show that there can exist a stable nonstationary equilibrium.