Modelling successive h-indices

Abstract

From a list of papers of an author, ranked in decreasing order of the number of citations to these papers one can calculate this author's Hirsch index (or h-index). If this is done for a group of authors (e. g. from the same institute) then we can again list these authors in decreasing order of their h-indices and from this, one can calculate the h-index of (part of) this institute. One can go even further by listing institutes in a country in decreasing order of their h-indices and calculate again the h-index as described above. Such h-indices are called by SCHUBERT [2007] "successive" h-indices.

In this paper we present a model for such successive h-indices based on our existing theory on the distribution of the h-index in Lotkaian informetrics. We show that, each step, involves the multiplication of the exponent of the previous h-index by 1/alpha where alpha > 1 is a Lotka exponent. We explain why, in general, successive h-indices are decreasing.

We also introduce a global h-index for which tables of individuals (authors, institutes,.) are merged. We calculate successive and global h-indices for the (still active) D. De Solla Price awardees.