POPULATION DISPERSION VS. CONCENTRATION IN A TWO‐REGION MIGRATION MODEL WITH ENDOGENOUS NATURAL AMENITIES*
研究发现，美国农村高自然禀赋县的人口长期分布趋于集中而非分散，通过构建包含劳动力流动、生产外部性和内生自然禀赋的两区域模型解释了这一现象。
ABSTRACT Contrary to the predictions of the basic spatial equilibrium model, the long‐run distribution of population across rural U.S. counties with high‐valued natural amenities has become relatively more concentrated versus dispersed. We provide an explanation by developing a two‐region model with mobile labor, production externalities and endogenous natural amenities. We find that strong preferences for natural amenities generally foster population dispersion. However, such preferences can also lead to population concentration when ecological degradation is low and man‐made capital is a relatively scarce input into natural amenity production. Investments that enhance natural amenities are found to reduce the divergence between the steady state and optimal outcomes.