  Self-promotion in science is ubiquitous but may not be exercised equally by
men and women. Research on self-promotion in other domains suggests that, due
to bias in self-assessment and adverse reactions to non-gender-conforming
behaviors (``pushback''), women tend to self-promote less often than men. We
test whether this pattern extends to scholars by examining self-promotion over
six years using 23M Tweets about 2.8M research papers by 3.5M authors. Overall,
women are about 28% less likely than men to self-promote their papers even
after accounting for important confounds, and this gap has grown over time.
Moreover, differential adoption of Twitter does not explain the gender gap,
which is large even in relatively gender-balanced broad research areas, where
bias in self-assessment and pushback are expected to be smaller. Further, the
gap increases with higher performance and status, being most pronounced for
productive women from top-ranked institutions who publish in high-impact
journals. Critically, we find differential returns with respect to gender:
while self-promotion is associated with increased tweets of papers, the
increase is smaller for women than for men. Our findings suggest that
self-promotion varies meaningfully by gender and help explain gender
differences in the visibility of scientific ideas.
