Changes in income inequality during the process of economic development and effective redistribution policy

Research Project

Project/Area Number	15K03487
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Economic policy
Research Institution	Kansai University
Principal Investigator	Kasuga Hidefumi 関西大学, 経済学部, 教授 (40310031)
Project Period (FY)	2015-04-01 – 2019-03-31
Project Status	Completed (Fiscal Year 2018)
Budget Amount *help	¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000) Fiscal Year 2018: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000) Fiscal Year 2017: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000) Fiscal Year 2016: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000) Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Keywords	所得分配 / 不平等 / 再分配政策 / 公共支出 / 海外援助 / 貧困の罠 / 所得不平等 / 人口転換 / 所得格差 / 再分配
Outline of Final Research Achievements	This study has investigated what factors determine income inequality, how inequality changes over time, and what policy can reduce inequality. To investigate the determinants of inequality, this study has used Japanese prefecture-level data. The regression results have shown that public spending reduces income inequality by providing employment opportunities for low-income households. In addition, to explain how inequality changes over time, this study has developed a theoretical model that focuses on infant mortality, and shown that a decrease in infant mortality reduces poverty but increases inequality because the supply of skilled workers increases and wage income stagnates. Finally, using data on foreign aid, this study has shown that spending for pro-poor projects can reduce income inequality and that the inequality-reducing effect is larger in poor countries.
Academic Significance and Societal Importance of the Research Achievements	本研究は、なぜ所得の不平等が発生し拡大するのか、不平等を是正するにはどのような政策が有効であるのかを明らかにしたものである。本研究では以下のような政策に関わる結果が得られた。日本のデータからは、公共支出の中でも雇用への効果が大きい公共投資を削減することが格差拡大につながっていることが示された。途上国のデータからは、貧困率の高い国では教育や保健衛生に関わる援助への配分を高めることが格差是正につながっていることが示された。これらは、内外の格差是正策立案の根拠として有用な経験的証拠となりうる成果といえる。