要旨：This study investigates coordination of binary choices on given specific social networks with incomplete information on random individual preference. Despite players' deterministic payoff is only influenced by local interaction with their neighborhoods, their strategies are affected both by direct and indirect interaction via diffusion of probabilistic belief on network. We proved that an equilibrium is robust one in which players' choices are biased to the advantageous alternative because of network externalities. Also, when uniformly distributed random preference is supposed, this model represents an unique equilibrium described by a Bonacich's centrality measure in which each player's choice is more agglomerated to the advantageous alternative if he is more central player in the network.

要旨：Long-term development of a social capability of regional preparedness against disaster requires both general knowledge and local knowledge; the former is developed to be scientific and systematized by professional researchers and practitioners, although it can not be appropriately applied in communities without the latter which includes local geographical features, characteristics of community members and theirs relationships and so on. This study formulates an economic growth model under disaster risk, where it exclusively focuses on two inherent process of knowledge development: “Opportunity-based learning (OBL)” and “Knowledge matching”. OBL is a concept that we have new findings whenever we are hit by disasters of unparalleled scales. In other words, we would never expect all the results beforehand by means of model analyses and simulations, and are therefore motivated to go for surveys immediately after disasters to obtain new problems to be solved. “Knowledge matching” is achieved by an appropriate meeting of a specialist and a community where the specialist’s expertise plays a crucial role. A search model is incorporated into the regional growth model to express the matching process of specialists and regions that results in “Knowledge matching”. The study develops a new type of Research and Development (R&D) model of innovation of disaster prevention.

要旨：This study explores the spatial pattern of industry dynamics in the counties in the Nagoya metropolitan area, Japan, during the period 1986-2006. The methods of exploratory spatial data analysis (ESDA) are applied to investigate spatial growth clusters of the manufacturing industries as well as the services. In particular, we introduce the spatial weight matrix that reflects both geographical and technological proximity into ESDA. The descriptive results based on the spatial statistics explicitly taking into account technological proximity identify a positive association between the industrial growth more clearly than do the statistical results based only on geographical proximity. It is also found that the local spatial statistics detect the positive multilayered growth clusters with different industrial composition and geographical scales.

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.

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