Evolution of research subjects in library and information science based on keyword, bibliographical coupling, and co-citation analyses

Yu-Wei Chang, Mu-Hsuan Huang,Chiao-Wen Lin

Scientometrics DOI 10.1007/s11192-015-1762-8

Abstract: This study involved using three methods, namely keyword, bibliographic coupling, and co-citation analyses, for tracking the changes of research subjects in library and information science (LIS) during 4 periods (5 years each) between 1995 and 2014. We examined 580 highly cited LIS articles, and the results revealed that the two subjects "information seeking (IS) and information retrieval (IR)" and "bibliometrics" appeared in all 4 phases. However, a decreasing trend was observed in the percentage of articles related to IS and IR, whereas an increasing trend was identified in the percentage of articles focusing on bibliometrics. Particularly, in the 3rd phase (2005-2009), the proportion of articles on bibliometrics exceeded 80 %, indicating that bibliometrics became predominant. Combining various methods to explore research trends in certain disciplines facilitates a deeper understanding for researchers of the development of disciplines.

Keywords: Library and information science; Keyword analysis; Bibliographical coupling; Co-citation

(摘要：本文利用关键词分析、文献耦合和共引分析方法对1995年到2014年（分成4个阶段，每5年为一个阶段）期间图书情报学研究主题的变化进行了相关研究。我们关注了580篇高被引文献，研究显示：“信息查找”、“信息检索”和“文献计量”在4个阶段都出现。但是，“信息查找”和“信息检索”的研究处于一个下降的趋势，而“文献计量”的论文数量处于一个上升的态势。尤其是在2005年到2009年期间，文献计量方面的论文增长超过了80%，这表明它占据了一个非常优势的地位。各种方法的综合应用更有利于深入观察某个学科的发展。)

Both relationships of bibliographical coupling and co-citation between two documents are created through a third document. When two documents are cited by a third document, a co-citation relationship exists between them. The more documents cite a pair of documents, the higher is the co-citation strength of the two documents (Small 1973). Similarly, when two documents cite the same document, they are bibliographically coupled (Kessler 1963). The higher the number of common documents cited by two documents, the higher is the bibliographic coupling strength of the two documents. A high value in both bibliographic coupling strength and co-citation strength indicates a similar subject relationship between the two documents.

文献耦合和共引分析都是基于两篇文献与第三篇文献之间的关系。共引分析是指两篇文献同时被第三篇文献引用。如果它们同一时被引的次数越多，那么它们的关系越密切。文献耦合是指两篇文献同时上用第三篇文献。同样，如果它们引用的共同文献数量越多，那它们的关系越密切。

Although both bibliographical coupling and co-citation analyses can be used to elucidate the intellectual structure of disciplines, researchers have preferred co-citation analysis. A few researchers have claimed that co-citation analysis is superior in displaying disciplinary structures to bibliographical coupling analysis (Bichteler and Eaton 1980; Sharabchiev 1989). However, bibliographic coupling has been proven to be an effective method for identifying changes in research topics (Zhao and Strotmann 2008, 2014). The number of studies using bibliographic coupling analysis has increased (Boyack and Klavans 2010; Ma 2012; Zhao and Strotmann 2014; Yan and Ding 2012). In addition, researchers are increasingly investigating intellectual structures of disciplines by using various bibliometric techniques and comparing the differences and similarities of results generated by various bibliometric techniques (A° stro¨m 2002; Boyack and Klavans 2010; Qiu, Dong, and Yu 2014; Yan and Ding 2012; Zhao and Strotmann 2014).

虽然文献耦合和区引分析常常用来阐释学科结构，而且研究人员更喜欢共引分析。但很少研究者说明，共引分析在展示学科结构方面要优于文献耦合。而文献耦合在识别研究主题变化方面要比共引分析更有效。利用文献耦合分析的研究成果数量在增加。另外，研究者正在利用各种文献计量技术来研究知识结构，同时也在关注不同文献计量技术之间的差异和相同之处。

注：关键词分析是词频统计结果的分析。