Who Crossed the Border? Self-Selection of Mexican Migrants in the Early Twentieth Century
利用1920年代边境登记中的身高数据作为移民质量的代理指标，研究发现墨西哥移民在身高上相对于墨西哥本土人口呈正向选择，但返回移民与永久移民在身高上无显著差异。
We estimate the self-selection of Mexican migrants into and out of the United States in the 1920s. Officials recorded migrant height on border crossing manifests, which we use to proxy migrant quality and to measure self-selection into migration in 1920. Migrants were positively selected on height compared to the Mexican population. We link these migrants to the 1930 U.S. and Mexican censuses to obtain samples of permanent and return migrants and to estimate the selection into return migration. Return migrants were not differentially self-selected on height relative to permanent migrants.