Mapping knowledge domains: Characterizing PNAS

Abstract

A review of data mining and analysis techniques that can be used for the mapping of knowledge domains is given. Literature mapping techniques can be based on authors, documents, journals, words, and͞or indicators. Most mapping questions are related to research assessment or to the structure and dynamics of disciplines or networks. Several mapping techniques are demonstrated on a data set comprising 20 years of papers published in PNAS. Data from a variety of sources are merged to provide unique indicators of the domain bounded by PNAS. By using funding source information and citation counts, it is shown that, on an aggregate basis, papers funded jointly by the U.S. Public Health Service (which includes the National Institutes of Health) and non-U.S. government sources outperform papers funded by other sources, including by the U.S. Public Health Service alone. Grant data from the National Institute on Aging show that, on average, papers from large grants are cited more than those from small grants, with performance increasing with grant amount. A map of the highest performing papers over the 20-year period was generated by using citation analysis. Changes and trends in the subjects of highest impact within the PNAS domain are described. Interactions between topics over the most recent 5-year period are also detailed.

Evolution and convergence of the patterns of international scientific collaboration

“…Overall, then, the categorization of basic and applied fields in the study here is coherent with the global structure of science detected predominantly in current literature (14,(17)(18)(19)(20)(21)(22)(23)(24)(25).…”

Mapping the structure of science through usage

“…a selection of journals for which Thomson's ISI has decided to publish citation and impact data. Possible future extensions of this work may rely on public sources of citation data such as Citeseer or arXiv to increase the relevance and scope of this work as shown by BOYACK (2004). In addition, the discussed analysis should be extended to the level of individual articles for a finer grained map of science.…”

“…From a social and political perspective it is therefore vital to build an understanding of its properties as a dynamic, social process. The scientific literature is rife with structural analysis and visualizations of the structure of science (CHEN & PAUL, 2001;NAGPAUL, 2002;BOYACK, 2004). The data sets used in such mappings rely mostly on citation 229 etc.…”

Mapping topics and topic bursts in PNAS

“…No ISI key words are available for papers published before 1991. MeSH terms have been joined to ISI records by using the procedure in Boyack (4). Papers without titles were excluded from the analysis, resulting in 4,699 papers.…”