A small world of citations? The influence of collaboration networks on citation practices

TL;DR

This study investigates how collaboration networks influence citation practices across disciplines, revealing limited tendency to cite nearby authors in the network beyond direct self-citations, with implications for bias and peer review.

Contribution

It introduces a network-based analysis of citation proximity, highlighting discipline-specific citation behaviors and their evolution over 50 years.

Findings

Low tendency to cite nearby authors in collaboration networks

Discipline differences in co-authorship and citation practices

Implications for bias in citation analysis and peer review

Abstract

This paper examines the proximity of authors to those they cite using degrees of separation in a co-author network, essentially using collaboration networks to expand on the notion of self-citations. While the proportion of direct self-citations (including co-authors of both citing and cited papers) is relatively constant in time and across specialties in the natural sciences (10% of citations) and the social sciences (20%), the same cannot be said for citations to authors who are members of the co-author network. Differences between fields and trends over time lie not only in the degree of co-authorship which defines the large-scale topology of the collaboration network, but also in the referencing practices within a given discipline, computed by defining a propensity to cite at a given distance within the collaboration network. Overall, there is little tendency to cite those nearby in the collaboration network, excluding direct self-citations. By analyzing these social references, we characterize the social capital of local collaboration networks in terms of the knowledge production within scientific fields. These results have implications for the long-standing debate over biases common to most types of citation analysis, and for understanding citation practices across scientific disciplines over the past 50 years. In addition, our findings have important practical implications for the availability of 'arm's length' expert reviewers of grant applications and manuscripts.