State affirmative action bans and STEM degree completions

This paper investigates the effect of statewide affirmative action bans on minority STEM degree completions at US public four-year colleges. The number of minority students completing STEM degrees at highly selective colleges falls by 19% five years after affirmative action bans, while there is no change in the total number of students completing STEM degrees. This indicates that a nontrivial number of minority students only admitted to highly selective colleges because of affirmative action graduate in STEM during periods of race preferences in college admissions. There is no convincing evidence of effects at moderately selective colleges. These findings speak to the recent debate about the extent to which minority students admitted to top ranked colleges due to affirmative action may have higher probabilities of graduating in the sciences if they had attended lower ranked colleges. Results are presented with the caveats that changes in race reporting caused by affirmative action bans may upwardly bias estimated effects, and that estimated aggregate effects may not fully capture all student-level responses.