Scientometrics

, Volume 84, Issue 2, pp 431–439 | Cite as

Probing the h-core: an investigation of the tail–core ratio for rank distributions

Article

Abstract

The set of citations received by a set of publications consists of citations received by articles in the h-core and citations received by articles in the h-tail. Denoting the cardinalities of these fours sets as C, P, CH and CT we introduce the tail-core ratio (CT/CH) and show that in practical cases this ratio tends to increase. Introducing further the k-index, defined as k = (C/P)/(CT/CH), we show that this index decreases in most practical cases. A power law model is in accordance with these practical observations.

Keywords

h-Index h-Core h-Tail Tail–core ratio v-Index k-Index 

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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2009

Authors and Affiliations

  1. 1.Department of Information Resources ManagementZhejiang UniversityHangzhouChina
  2. 2.Institute of Scientific and Technical Information of ChinaBeijingChina
  3. 3.Department of Industrial Sciences and TechnologyKHBO (Association K.U.Leuven)OostendeBelgium
  4. 4.Department of MathematicsK.U.LeuvenHeverlee, LeuvenBelgium

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