Women in science and academia still face an uphill battle to receive equal recognition for their work. They now earn about half of all degrees, but top positions,funding, and even authorship of papers remain skewed in favour of men. Part of the reason women could have a difficult time getting their voices heard in academia is that men are busy talking—about themselves.
A new study led by sociologists at Stanford University and uploaded to the Arxiv preprint server shows that, since the 18th century, male academics cite their own papers on average 56 percent more than their female counterparts. And although you might expect this trend to level off as women occupy more tenure track positions and publish more papers, the opposite appears to be true: In the past two decades, the rate of self-citation among men was 70 percent higher than that of women.
This graph shows the mean number of self-citations for men and women, per authorship, over time. Image: King et al/Arxiv
An increased propensity to point to one’s own work—“manciting,” if you will—is no small thing when the number of citations a paper has is often used as a proxy to measure a scientist’s importance by both peers and employers.
“I think there's this idea that all we need to do is get more women into science and that will solve all the problems,” said Molly King, a PhD candidate and lead author of the study. “But if women aren't citing themselves, there's a further visibility gap that comes from that, which makes it harder for women to get tenure. So it's making it even harder for women to narrow the gender gap in academia.”
This shows the ratio of men’s to women’ self-citations per authorship. If they were equal, they’d be at 1.0. Image: King et al/Arxiv
Self-citation, or referencing a work that has an author in common with your own paper, makes up nearly 10 percent of total citations across all 1.5 million papers on the academic database JSTOR, which the researchers used for their study. King noted that a previous study looking at over half a million scientific papers concluded that each self-citation leads to nearly three additional total citations of an author’s work over the next few years, due to increased visibility—meaning that pointing people to your own work can have a multiplicative effect.
“Women aren't getting the credit from themselves, or the credit that accrues to them from others, and that's a pretty significant gap,” said King.
Of course, pointing out your own work isn’t always pure self-promotion; responsible scholars should always reference extensively and accurately. But it’s not clear, in that case, why men self-cite so much more often than women.
"What's most surprising is there's no decrease over time"
The researchers speculate that men may self-cite more because they tend to evaluate their own abilities more positively than women, and because women may face a social penalty for self-promoting: They refer to an influential study from NYU showing that when women succeed at male-dominated tasks, they are perceived more negatively.
There are some limitations to the study, which, as a pre-print, is open to public comments while it is being reviewed for publication. King says male academics tend publish more papers, possibly leaving them with more work to cite. And men also tend to be more specialized, meaning that with a narrower range of literature available they have no choice but to point to their own work.
Still, the researchers think that such a consistent and long-running trend deserves further scrutiny, especially as the gap doesn’t seem to be narrowing.
“What's most surprising is there's no decrease over time,” said King. “We were expecting to find that, as women have entered science and gotten into more senior positions, we would see that ratio get smaller, and we're still not entirely clear on why that isn't the case. I look forward to trying to figure it out.”