Theoretical study of decentralized development of infrastructure by local governments

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K01561
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 07040:Economic policy-related
• Research Institution: Tohoku University
• Principal Investigator: Itoh Ryo 東北大学, 情報科学研究科, 准教授 (30516000)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 災害リスク / 災害適応投資

Outline of Final Research Achievements

We　investigated decision making for investment in infrastructure to avoid the risk of natural disasters in the transportation sector, and designed a system to optimize the investment. As a result of an analysis focusing on the independence of natural disasters and risk sharing between infrastructures, if the disaster is widespread and the spatial independence is low (e.g., climate change), investment by a private company Is less than public investment, but spatially local ones (earthquakes, etc.) have the opposite tendency.
We have also developed a model for welfare analysis in which the effects of transportation infrastructure investment spread to the entire economy through interregional intermediate material transactions. As a result of applying a linear approximation method based on the latest nonlinear international trade model, an induction system similar to the Leontief inverse matrix was obtained.

Free Research Field

交通経済学、都市経済学

Academic Significance and Societal Importance of the Research Achievements

インフラ投資が地方分権や私的企業によって行われる際の、社会的歪みについて考察した。特に、災害を回避する投資については、災害の種類（地震、気候変動など）によって異なる空間的局所性と独立性が、過大投資と過小投資のどちらにつながるかを明らかにしたことは、政策提言上重要であると考えられる。また、インフラ投資の効果をミクロ経済学的に厳密かつ扱いやすい誘導系として導出したことで、政策分析のツールを生み出した。