Shota FujishimaAssistant Professor 2013-
Division of Spatial Socio-Economic Research （Further information is available at http://sfujishima.main.jp/）
1. Mechanism Design for Urban Congestion Problems
Taxation forms an efficient means to circumvent urban problems such as traffic congestion and environmental pollution. In the case of traffic congestion, for example, the government has to determine the value of time loss because of traffic congestion to set the optimal tax rate; however, because people’s value of time is deemed private, the government has no access to it. Therefore, I design a scheme in which the government can gradually adjusts the tax rate toward the optimal rate, rather than simply following a predetermined tax rate. Specifically, the government adjusts the tax rate by observing how individuals respond to a tax in every period and accumulating the necessary information to formulate an optimal tax rate. Implementing such a scheme in the real world will involve the availability of detailed spatial data such as traffic distribution changes over time. I would like to investigate the technical aspects of this scheme by working not only with economists but also researchers from other fields such as engineering and computer sciences.
2. Economic Growth and Urban Agglomeration
Economic growth closely interacts with the dynamic evolution of spatial population distribution. For example, in the real world it is commonly observed that at an early stage of economic development, population is agglomerated and high economic growth is achieved; however, at a late stage, population is dispersed, thereby escaping from the downsides of urban agglomeration such as traffic congestion and environmental pollution. Most previous research on urban growth, however, focuses on cases in which the spatial population distribution is fixed over time. Therefore, I construct an urban growth model that addresses the dynamic interactions between economic growth and urban agglomeration.
3. Structurally Testable Urban Economic Models
In the area of spatial economics, theoretical research has offered several interesting insights into the spatial aspects of economic activities. However, most of these studies are not fully compatible with empirical testing, and therefore there still exists a large gap between theory and empirical research. Generally, spatial economic models are complex models that have both general equilibrium effects and strategic interactions through location choices. In view of recently developed techniques of structural estimation, I seek to construct structurally testable urban economic models.