An interdisciplinary research team, led by Molly M. King, Ph.D. candidate in sociology, has found that men are more than twice as likely as women to cite themselves in any discipline.

Self-citation occurs when authors reference previous works they also authored, and each self-reference contributes to citation counts, which King said are often used to determine hiring and tenure decisions. According to King, gender gaps in self-citation counts likely contribute to the gender gap in academia representation.

King co-authored the paper with Shelley Correll, professor of sociology at Stanford; Carl T. Bergstrom, professor of biology at University Washington; Jevin D. West, assistant professor of information at University of Washington; and Jennifer Jacquet, professor of environmental studies at New York University.

Their study utilized a data set in the scholarly database JSTOR of 1.5 million research papers from 1779-2011 and multiple disciplines, including biology, sociology, economics and law. The researchers found self-citation accounts for nearly 10 percent of all references and men self-cite 56 percent more than women. Contrary to the decrease in gender difference the researchers expected to discover, over the last two decades the gender gap in self-citation has remained high, with men self-citing 70 percent more than women, compared to the previous overall average of 56 percent.

The team presented several hypotheses for the citation inequality, including the possibility that men think more highly of themselves, face less backlash with self-promotion and generally publish more papers early in their careers. Men also tend to specialize more and might publish more of the types of papers that would make sense to self-cite.

“Women are significantly underrepresented as authors of single-authored papers and -– on papers with three or more authors –- in the prestigious positions of first and last author,” the study found.

West proposes the public and organizations should evaluate the evidence to make informed promotion, salary and hiring decisions.

“What’s important is hiring communities and funders, like the National Science Foundation and National Institutes of Health … should be aware that self-citation counts can be biasing the results that they’re trying to use to make decisions,” West said. “People should realize there is a big gender difference in these citations and be aware.”

King said the research findings do not reveal the cause of the self-citation gender gap, but the importance of the study is in the awareness it raises for gender differences in the academic workplace.

“The major contribution of our work is looking at the important phenomenon of inequality, uncovering the large [gender] gap and doing so with an unprecedentedly large data set of 200 years,” King said.

The researchers said the public should not draw conclusions that self-citation is an improper practice or that the solution is for women to self-cite more in the future.

“Self-citation is often quite appropriate and can help researchers follow the historical path of a research program,” King said. “There’s no correct amount of citation, but one way to remedy the inequality would be to remove counts of self-citation for individual scholars.”

West said that the research’s large multidisciplinary scale allows this paper to add to the growing body of evidence that there is a connection between citation patterns and the gender issues the research community needs to address.

As plans for further research continue, researchers are looking to expand the data set to include more disciplines, such as computer science and medicine, and to develop a disambiguated author set that would distinguish authors with the same name. They also plan to study whether women are more likely to publish with women and men with men.
Contact Caitlin Ju at ju.caitlin ’at’ gmail.com.