The effects of urban transportation policies, such as transportation infrastructure improvements, differ significantly in the short- and long-run. This is because the short-run impact of alleviating traffic congestion can change the spatio-temporal agglomeration structure of economic activities (location and size of urban centers, distribution of work start time) in the long run. However, there is no approach for examining the long-run effects. In this study, we conducted theoretical and empirical studies to clarify the spatio-temporal agglomeration mechanism of economic activities. We then develop a method for evaluating the long-run effects of the policies.
交通基盤整備などの都市交通政策の効果は,短期/長期で大きく異なる.これは,短期的に発現する渋滞・混雑緩和効果が,長期的には経済活動の時空間集積構造(都心の位置・規模,始業時刻分布)を大幅に変化させるためである.したがって,社会的要請の強い“政策の長期的効果(ストック効果)の把握”には,その影響の適切な予測・評価が必要となる.そこで,本研究では,経済活動の時空間集積メカニズムを理論・実証両面から解明した.さらに,その知見を基盤に,“政策の長期的効果の定量的評価”のための分析手法を開発した.