Academic In-Group Bias: An Empirical Examination of the Link between Author and Journal Affiliation

Abstract

Do academic journals favor authors who share their institutional affiliation? To answer this question we examine citation counts for articles published in four leading international relations journals during the years 1995-2010. We use a difference-in-differences methodology to compare citation counts for articles written by “in-group members” (authors affiliated with the journal’s publishing institution) versus “out-group members” (authors not affiliated with that institution). Articles written by in-group authors received 9 to 19 fewer Web of Science citations when published in their home journal (International Security or World Politics) vs. an unaffiliated journal, compared to out-group authors. These results are mainly driven by authors who received their PhDs from Harvard or MIT. The findings show evidence of a bias within some journals towards publishing papers by faculty from their home institution, at the expense of paper quality, as measured by citations.