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Item-time-dependent Lotkaian informetrics and applications to the calculation of the time-dependent -index and -index

✍ Scribed by L. Egghe

Publisher
Elsevier Science
Year
2007
Tongue
English
Weight
251 KB
Volume
45
Category
Article
ISSN
0895-7177

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✦ Synopsis

The model for the cumulative nth citation distribution, as developed in [L. Egghe, I.K. Ravichandra Rao, Theory of first-citation distributions and applications, Mathematical and Computer Modelling 34 (2001) 81-90] is extended to the general source-item situation. This yields a time-dependent Lotka function based on a given (static) Lotka function (considered to be valid for time t = ∞). Based on this function, a time-dependent Lotkaian informetrics theory is then further developed by e.g. deriving the corresponding time-dependent rank-frequency function.

These tools are then used to calculate the dynamical (i.e. time-dependent) g-index (of Egghe) while also an earlier proved result on the time-dependent h-index (of Hirsch) is refound. It is proved that both indexes are concavely increasing to their steady state values for t = ∞.

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