The use of Cited Half Life to assess obsolescence evolution in different research domains: an empirical test

Among the bibliometric indicators dealing with ageing of scientific literature, Cited Half Life (CHL) has a relevant position, as stated by ISI-WoS. The present work aims at performing an empirical test of the different features of CHL with particular regard to its evolution in the two domains of Sciences and Social sciences in ISI-WoS. For this purpose, first a sample of Subject categories is extracted. Then, mean and median for every year from 1999 onwards are calculated. Finally, trends and non-parametric correlation coefficients for all the values are obtained. The aim is to devise whether strong differences exist between the two domains, and surreptitiously to assess the meaningfulness of the use of CHL as an indicator of ageing of scientific literature. At the end of the paper the results are described and, accordingly, conclusions are drawn.