The Impact of City Contracting Set-Asides on Black Self-Employment and Employment
研究美国城市在1980年代启动的少数族裔企业合同预留计划，发现该计划显著提高了黑人男性自雇率，缩小了种族差距3个百分点，但对就业差距的影响不确定。
In the 1980s, many US cities initiated programs reserving a proportion of government contracts for minority-owned businesses. The staggered introduction of these set-aside programs is used to estimate their impacts on the self-employment and employment rates of African American men. Black business ownership rates increased significantly after program initiation, with the black-white gap falling 3 percentage points. The evidence that the racial gap in employment also fell is less clear as it depends on assumptions about the continuation of preexisting trends. The black gains were concentrated in industries heavily affected by set-asides, and they mostly benefited the better educated.