Knowledge that Transforms

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.

Military assignment mechanisms provide a unique opportunity to estimate the impact of high-performing mentors on job advancement of their subordinates. Combining US Army administrative data with officer evaluation reports, we find that high-performing mentors positively affect early junior officer promotion and that early promotion probabilities rise as the duration of the high-quality mentorship increases. These effects are largest for high-ability protégés. Junior officers who were exposed to multiple high-performing mentors did not experience an additional increase in promotion rates.