Probing the h-core: an investigation of the tail–core ratio for rank distributions
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.
Keywordsh-Index h-Core h-Tail Tail–core ratio v-Index k-Index
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