Abstract
We investigate whether competitive selection processes generate gender inequality in the context of a prestigious fellowship program in Spain. We find a clear pattern of gender balancing: in each field of study, reviewers give higher scores to observationally similar candidates of the minority gender. Because, except for STEM, all fields are female-dominated, this results in a female penalty. We also show that gender balancing arises in the first stage of the selection process, where reviewers assign quantitative scores to all applications. Our findings suggest that reviewers have a preference for gender equality in outcomes within their field.