How the Other Half Died: Immigration and Mortality in U.S. Cities
研究1920年代美国移民配额制对城市死亡率的影响，发现配额减少移民的城市死亡率持续下降，主要源于传染病死亡减少，且效果在移民居住拥挤、公共卫生资源紧张的城市更显著。
Abstract Fears of immigrants as a threat to public health have a long and sordid history. At the turn of the 20th century, when immigrants made up one-third of the population in crowded American cities, contemporaries blamed high urban mortality rates on the newest arrivals. We evaluate how the implementation of country-specific immigration quotas in the 1920s affected urban health. Cities with larger quota-induced reductions in immigration experienced a persistent decline in mortality rates, driven by a reduction in deaths from infectious diseases. The unfavourable living conditions immigrants endured explains the majority of the effect as quotas reduced residential crowding and mortality declines were largest in cities where immigrants resided in more crowded conditions and where public health resources were stretched thinnest.