Specialization, field distance, and quality in economists’ collaborations

Abstract

• Co-authors have become geographically more distant but much closer in terms of field distance (overlap between co-authors’ research fields) over the last couple of decades. • A smaller field distance is significantly related to the quality of co-authors’ joint work. • Geographically distant collaborations and same location collaborations have significantly different field distances on average and since field distance is negatively related to research quality, same location collaborations are of less quality. • Highly specialized authors are more likely to team up with co-authors that have a very close field distance to them and such closeness is related to a high quality of collaboration output. • Highly specialized co-authors, however, find it harder to get into best ranked journals and get high citations so that the total effect of specialization is negative on collaboration impact. • High quality interdisciplinary research that is created by the collaboration of authors in separate fields with completely separate expertise might only exist in dreams of grant committees and in the strong imagination of faculty administrators, but not in the real world, at least not in our data. We analyze economics PhDs’ collaborations in peer-reviewed journals from 1990 to 2014 and investigate such collaborations’ quality in relation to each co-author’s research quality, field and specialization. We find that a greater overlap between co-authors’ previous research fields is significantly related to a greater publication success of co-authors’ joint work and this is robust to alternative specifications. Co-authors that engage in a distant collaboration are significantly more likely to have a large research overlap, but this significance is lost when co-authors’ social networks are accounted for. High quality collaboration is more likely to emerge as a result of an interaction between specialists and generalists with overlapping fields of expertise. Regarding interactions across subfields of economics (interdisciplinarity), it is more likely conducted by co-authors who already have interdisciplinary portfolios, than by co-authors who are specialized or starred in different subfields.