Migration, Housing Constraints, and Inequality: A Quantitative Analysis of China

We investigate the role of migration and housing constraints in determining income inequality within and across Chinese cities. Combining microdata and a spatial equilibrium model, we quantify the impact of the massive spatial reallocation of workers and the rapid growth of housing costs on the national income distribution. We first show several stylized facts detailing the strong positive correlation between migration inflows, housing costs, and imputed income inequality among Chinese cities. We then build a spatial equilibrium model featuring workers with heterogeneous skills, housing constraints, and heterogeneous returns from housing ownership to explain these facts. Our quantitative results indicate that the reductions in migration costs and the disproportionate growth in productivity across cities and skills result in the observed massive migration flows. Combining with the tight land supply policy in big cities, the expansion of the housing demand causes the rapid growth of housing costs and enlarges the inequality between local housing owners and migrants. The counterfactual analysis shows that if we redistribute land supply increment by migrant flow and increase land supply toward cities with more migrants, we could lower the within-city income inequality by 14% and the national income inequality by 18%. Meanwhile, we can simultaneously encourage more migration into higher productivity cities.