Mapping the backbone of science

Abstract

This paper presents a new map representing the structure of all of science, based on journal articles, including both the natural and social sciences. Similar to cartographic maps of our world, the map of science provides a bird's eye view of today's scientific landscape. It can be used to visually identify major areas of science, their size, similarity, and interconnectedness. In order to be useful, the map needs to be accurate on a local and on a global scale. While our recent work has focused on the former aspect, 1 this paper summarizes results on how to achieve structural accuracy.Eight alternative measures of journal similarity were applied to a data set of 7,121 journals covering over 1 million documents in the combined Science Citation and Social Science Citation Indexes. For each journal similarity measure we generated two-dimensional spatial layouts using the force-directed graph layout tool, VxOrd. Next, mutual information values were calculated for each graph at different clustering levels to give a measure of structural accuracy for each map. The best co-citation and inter-citation maps according to local and structural accuracy were selected and are presented and characterized. These two maps are compared to establish robustness. The inter-citation map is then used to examine linkages between disciplines. Biochemistry appears as the most interdisciplinary discipline in science.

Visualizing the marrow of science

“…In contrast, Leydesdorff (2004aLeydesdorff ( , 2004b classified world science using the graph-analytical algorithm of biconnected components in combination with JCR 2001. Boyack, Klavans, and Börner (2005) applied eight alternative measures of journal similarity to a dataset of 7,121 journals covering over 1 million documents in the combined Science Citation and Social Science Citation Indexes, to show the first global map of science using the force-directed graph layout tool VxOrd. Samoylenko Chao, Liu, and Chen (2006) proposed an approach through the construction of minimum spanning trees of scientific journals, using the Science Citation Index from 1994 to 2001.…”

How are topics born? Understanding the research dynamics preceding the emergence of new areas

“…To this end, we represent topics and their relationships in a certain time frame as a graph in which nodes are topics and edges represent their cooccurrences in a sample of publications. This is a common representation for investigating topic dynamics (Boyack, Klavans & Börner, 2005;Leydesdorff, 2007;Newman, 2001). In the following we will refer to it as topic graph or topic network.…”

Analysis of the citation impact of national journals toward SCIE journals on JCR ranking

“…Apart from citation relationship, co-word analysis method has been developed and utilized for co-author relationship and keyword relationship analyses (Liu, Hu, and Wang 2012). Small and Garfield (1985) developed the global map of science based on the co-citation analysis in SCIE and SSCI database, and scholars have worked on the knowledge organization analysis in disciplines based on the map of science (Boyack, Klavans and Börner 2005).…”