Abstract: Education and labor mobility are key drivers in the production of human capital, fundamental to economic development. In the U.S., the varying skill production efficiencies of state-specific education systems and the dynamics of worker migration shape human capital of states, influencing economic outcomes at both the state and national levels. This paper develops a novel dynamic spatial general equilibrium model with overlapping generation framework in which heterogeneous individuals accumulate human capital and move across states. Calibrated to the U.S. economy, the model illustrates how variations in education efficiency lead to substantial crossstate income disparities and shows that internal migration can notably boost output in states with lower education efficiencies. At the national level, free mobility of workers yields a 6.9% output gain. Moreover, the model suggests that variations in human capital account for 46.6% of the state variation per capita output. Applying the calibrated model to analyze the Obama Administration’s Race to the Top initiative finds that the $4.1 billion grant spurred a 0.2% increase in U.S. GDP, mostly benefiting the grant-winning states and their neighbors. Additionally, alternative grant allocation experiments show that strategic reallocation of education grants, considering state skill production efficiencies, could further increase national GDP gains without necessarily worsening state income disparities.

Abstract: Do central slums provide essential economic and social benefits to the poor? We collected bespoke data for 5,000 households to study mass forced clearances in Addis Ababa. Evictees were offered alternative subsidized housing further from the center. Exploiting sharp clearance zone boundaries, regression-discontinuity estimates show negative impacts on social networks, but positive impacts on work, earnings, housing quality and environmental amenity. Relocating households close to their ex-ante neighbors eliminates social costs. Slums are not essential: relocation policies can be designed to fully compensate residents, and the sale value of cleared land more than covers the cost.

要旨：本報告は、前近代日本における都市人口の超長期推計とその変動の分析を試みるものである。1万人を閾値とした人口規模を中心に、各時代の都市人口と都市化率の推移を検討した。結果、古代律令国家の成立、中世市場経済の萌芽、近世における徳川幕府による国内秩序の確立や農村工業の進展といった、各時期の社会経済の変化と都市化の画期の関係が確認された。また、人口規模が1万人以下の中小都市においても、中世からの市、湊、宿などの町場の進展が確認され、そうした都市群は近世においても列島の経済成長に重要な役割をはたした。今後は、閾値の柔軟化や、単体の都市ではない広域的な都市構造の動態把握など、多面的な研究視座が求められる。