Citation Analysis: Bibliographic Coupling vs Co-citation Analysis

Citation Analysis: A citation can be defined as ‘a reference to a book, article, web page or other published or unpolished item that includes sufficient details to uniquely identify that item’.  In other words, a citation is a bibliographic reference or a footnote, quoted by an author for his writing. It helps to establish a connection between two documents. Citations are generally represented in the form of bibliographies, notes, and further readings. 

When one author cites another author, a connection is established between them. Citation analysis uses citations in scholarly works to establish that connections (links) with other works or other researchers. Thus, citation analysis is a method of finding frequency, patterns, and graphs of citations in books and articles. It helps to track the works of authors, the impact of papers and trajectory of research ideas by measuring citation counts in key research databases and online sources.

Citation analysis is commonly used to measure the relative importance or impact of an author, an article or a publication by counting the number of times that author, article, or publication has been cited by others. It helps researchers to determine how frequently a work has been cited in articles and is an invaluable tool for any literature review.

Citation analysis commonly helps researchers to: Find out the reach of their research Identify patterns in the way their work is being used Benchmark themselves against their peers Add weightage & reputation to their resumes when applying for grants and promotions

Citation analysis is one of the most widely used methods of bibliometrics. There are several tools available for citation analysis, i.e. Web of Science (WoS), Scopus, Google Scholar, Microsoft Academic.

Google's PageRank is based on the principle of citation analysis and is used to measure the importance of website pages.  PageRank, developed by Larry Page and Sergey Brin in 1996 and named after Larry Page, one of the founders of Google, is a link analysis algorithm used by Google to rank web pages in their search results. 

Bibliographic coupling, Co-citation analysis and Author Co-citation Analysis are association measures based on citation analysis.

Bibliographic Coupling: ‘Bibliographic Coupling’ is one of the earliest citation analysis methods for document similarity measure. The concept was first introduced in 1963 by M. M.  Kessler of Massachusetts Institute of Technology (MIT). Two documents are bibliographically coupled if they both cite one or more documents in common. In other words, bibliographic coupling emerge when two works reference a common third work in their bibliographies. We can say the coupling strength is higher when more citations, the two referring works have in common. This coupling also determines the subject similarity of the two works. Bibliographic coupling is equally valuable in all fields of research as it helps the researchers to find related research done in the past (retrospective).

Bibliographic Coupling	M. M. Kessler	1963
Co-citation Analysis	Henry Small & Irina Marshakova	1973
Author Co-citation Analysis	Howard White & Belver Griffith	1981

Co-Citation Analysis: Henry Small and Irina Marshakova are credited for introducing the concept of ‘co-citation analysis' in 1973. This method overcomes the shortcomings of bibliographic coupling by considering a document’s incoming citations to assess similarity, a measure that can change over time. Co-citation coupling is defined as ‘the frequency with which two documents are cited together by other documents’. In short,  the  two  documents  are  said  to  be  co-cited  when  they  both  appear  in  the reference list of a third document. The more co-citations two documents get, the higher their co-citation strength, and the more likely they are semantically related.

Elsevier’s web-based research analytics tool ‘SciVal’ is based on the technique of co-citation analysis.

Author Co-Citation Analysis (ACA): Author Co-citation Analysis was introduced by Howard White and Belver Griffith in 1981. It can be defined as ‘a bibliometric tool that analyses the relationships of pairs of cited authors within source documents’.

SELF CHECK EXERCISES

1.       Citation analysis helps in ___.

A.      Identification of core documents

B.      Subject indexing

C.      Descriptive cataloguing

D.      Selective Cataloguing

2.       ‘Bibliographic Coupling’ was first advocated by:

A.      B. K. Sen

B.      S. R. Ranganathan

C.      M. M. Kessler

D.      S. C. Bradford

3.       Who among the following at first introduced ‘co-citation analysis?

A.      Henry Small and Irina Marshakov

B.      Vickery

C.      T. C. Craven

D.      Nalimov and Mulchenkov

4.       PageRank- a link analysis algorithm was developed by __.

A.      Larry Page and Sergey Brin

B.      Gabriel Pinski and Francis Narin

C.      Tim Berners-Lee

D.      Howard White and Belver Griffith