Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
To reduce the gender gap in science fields, policymakers often propose providing women with mentoring by female scientists. However, there is no clear evidence on whether one-on-one mentor gender influences women’s STEM participation. We exploit a unique setting where students are randomly assigned to academic advisors—who are also faculty members—in their freshman year of college. Advisors help students select courses and decide on a major. We find that having a female rather than a male science advisor substantially increases the likelihood that women enroll and graduate with STEM degrees. A nonscience advisor’s gender has no impact on students’ major choice.