讲座主题：Transportation Costs, Ability Sorting, and the Agricultural Productivity Gap
摘 要：This paper proposes a novel explanation for the large labor productivity gap between agriculture and non-agriculture in developing countries. I interpret the productivity gaps as reflecting high ability workers sort into non-agriculture while low ability workers sort into agriculture. The sorting mechanism builds on two ingredients: lower food prices for agricultural workers due to transportation costs and declining food expenditure shares in income due to subsistence food requirement. Low ability (income) workers value lower food prices more because they spend a larger fraction of their income on food. The sorting mechanism has larger effects in developing countries as these countries have higher transportation costs and higher expenditure share of food. I formalize the idea in a two-sector multi-region general equilibrium model. Quantitative analysis shows that the ability sorting mechanism can explain around 30% of the labor productivity gap in Malawi relative U.S. Model predictions are tested using a detailed household survey from Malawi.