Quantitative evaluation of gender bias in astronomical publications from citation counts

  • Nature Astronomy 1, Article number: 0141 (2017)
  • doi:10.1038/s41550-017-0141
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Numerous studies across different research fields have shown that both male and female referees consistently give higher scores to work done by men than to identical work done by women 1,2,3 . In addition, women are under-represented in prestigious publications and authorship positions 4,5 and women receive ~10% fewer citations 6,7 . In astronomy, similar biases have been measured in conference participation 8,9 and success rates for telescope proposals 10,11 . Even though the number of doctorate degrees awarded to women is constantly increasing, women still tend to be under-represented in faculty positions 12 . Spurred by these findings, we measure the role of gender in the number of citations that papers receive in astronomy. To account for the fact that the properties of papers written by men and women differ intrinsically, we use a random forest algorithm to control for the non-gender-specific properties of these papers. Here we show that papers authored by women receive 10.4 ± 0.9% fewer citations than would be expected if the papers with the same non-gender-specific properties were written by men.

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We thank J. Woo for giving detailed comments on the manuscript. We acknowledge the stimulating comments given to us by M. Urry, R. Schubert, R. Marino, B. Trakhtenbrot, I. Moise and E. Pournaras. We thank A. Bluck for proofreading the manuscript. We acknowledge support from the Swiss National Science Foundation. This research made use of the National Aeronautics and Space Administation’s Astrophysics Data System, the arXiv.org preprint server and the Python plotting library Matplotlib 21 .

Author information


  1. Institute for Astronomy, Department of Physics, ETH Zurich, CH-8093 Zurich, Switzerland

    • Neven Caplar
    • , Sandro Tacchella
    •  & Simon Birrer


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N.C. initiated the project and carried out the data analysis. S.T. created the name-matching algorithm and prepared the sample. S.B. created the algorithm that matched the authors with their geographical location. N.C. and S.T. wrote the paper. All authors discussed the results and commented on the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Neven Caplar.

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    Supplementary Information

    Supplementary Figures 1–3 and Supplementary Table 1.