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Ratios of h-cores,h-tails and uncited sources in sets of scientific papers and technical patents
Authors:Joan Q. Liu  Ronald Rousseau  Mona S. Wang  Fred Y. Ye
Affiliation:1. Library of Zhejiang University, Hangzhou, China;2. KHBO (Association KU Leuven), Faculty of Engineering Technology, Zeedijk 101, B-8400 Oostende, Belgium;3. KU Leuven, Department Mathematics, Celestijnenlaan 200B, B-3000 Leuven (Heverlee), Belgium;4. Universiteit Antwerpen, IBW, Venusstraat 35, B-2000 Antwerpen, Belgium;5. Department of Information Resource Management, Zhejiang University, Hangzhou, China;6. School of Information Management, Nanjing University, Nanjing, China
Abstract:Five ratios RH, RT, SH, ST and SZ derived from the three-part division of a set of sources in h-core, h-tail and uncited sources are defined. Dynamic changes in the three independent ratios RH, SH and SZ are studied for six selected topics. Data about these topics are obtained from the Web of Science for scientific papers and Derwent Innovations Index for technical patents. It is observed that all RH- and SH-values decrease when the time span widens, while SZ stays the same or increases; and that all RH- and SH-values for papers are larger than the corresponding values for patents. The shifted Lotka distribution is used in a theoretical interpretation of these empirical phenomena.
Keywords:
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