Bibliographic coupling 
Documents are said to be bibliographically coupled if they share one or more bibliographic references. The concept of bibliographic coupling was introduced by Kessler (1963) who demonstrated the existence of the phenomenon and argued for its usefulness as an indicator of subject relatedness. The major theoretical criticism of this notion appeared soon after in a one-page article by Martyn (1964, p. 236) who sagaciously observed that there is no guarantee that two bibliographically coupled documents (A) and (B) cite the same piece of information in (C). He also observed that even if (A) and (B) cite the same piece of information in (C) we do not know the size of the conjunction and therefore, considering now the conjunction of two other documents (M) and (N), we may not equate (A)Ç(B) with (M)Ç(N). These observations led Martyn to conclude that a bibliographic coupling is merely an indication of the existence of the probability, value unknown, of relationship between two documents rather than a constant unit of similarity. His conclusion finds empirically support in Vladutz & Cook’s (1984) results. In their validation study, a random selection of 10.000 articles from the SCI was coupled with papers from the entire SCI database and lists of the three most strongly bibliographically coupled items were compiled. Professional indexers were then asked to assess the relatedness of these papers for a random sample of 300 lists. The indexers were merely able to report some degree of subject relatedness in little more than 85% of the cases, which decreased to 81% when the frequency of occurrence in the entire database and the length of the reference lists were both taken into account. It consequently seems reasonable to assume that such quantitative meters provide more valid results in some areas as opposed to others. Virgo (1971, p. 289), for instance, anticipates that the critical threshold value for the coupling strengths possibly varies from field to field and even within fields, and Weinberg (1974) predicts that bibliographic coupling should work best for repetitive literature (e.g., review articles) because such literature often cite a lot of older works.





Jarneving, B. (2006). The Combined Application of Bibliographic Coupling and the Complete Link Cluster Method in Bibliometric Science Mapping. Borås: Valfrid. (Dissertation).

Kessler, M. M. (1963). Bibliographic coupling between scientific papers. American Documentation, 14: 10-25.


Martyn, J. (1964). Bibliographic coupling. Journal of Documentation, 20(4): 236.


Virgo, J. A. (1971). The review article: Its characteristics and problems. The Library Quarterly, 41(4): 275-291.


Vladutz, G. & Cook, J. (1984), Bibliographic coupling and subject relatedness. Proceedings of the American Society for Information Science, 21: 204-207.


Weinberg, B. H. (1974). Bibliographic coupling: A review. Information Storage and Retrieval, 10: 189-196.


See also: Co-citation

Jeppe Nicolaisen