Loet Leydesdorff

Count highly-cited papers instead of papers with h citations: use normalized citation counts and compare “like with like”!

Teixeira da Silva and Dobránszki (Scientometrics. https://doi.org/10.1007/s11192-018-2680-3, 2018) describe practical problems in using the h-index for the purpose of research evaluation. For example, they discuss the h-index differences among the bibliometric databases. In this Letter to the Editor, we argue for abstaining from using the h-index. One can use normalized indicators instead.

Data-Mining the Foundational Patents of Photovoltaic Materials: An Application of Patent Citation Spectroscopy

We apply Patent Citation Spectroscopy (PCS)--originally developed as Reference Publication Year Spectroscopy for studying landmarks and milestones in scientific literature--to patent literature classified into the nine Y-subclasses of the Cooperative Patent Classification (CPC) that describe material photovoltaic technologies. For this study we extended the routine with the option to use the advanced search queries at PatentsView. On the basis of two normalizations of the longitudinal distribution of the publication years of the patents cited by the retrieved patents, the routine (at this http URL) provides a best guess of the foundational patent for the subject specified in the string. In five of the nine cases, we found corroborating evidence for the foundational character of the patent indicated by the routine.

Further steps in integrating the platforms of WoS and Scopus: Historiography with HistCite™ and main-path analysis

The program HistCite™ enables an analyst to identify significant works on a given topic using the citation links between them diachronically. However, using Scopus data for drawing historiograms with HistCite™ has hitherto been a problem. In the new version of the program CRExplorer, one can translate citation data from Scopus to WoS formats (or vice versa) and then import the data into HistCite™. In this brief communication, we demonstrate these options using the papers of Eugene Garfield (1925-2017) in Scopus for main-path analysis. The two historiograms are considerably different: unlike the WoS set, the networked connections between the time lines are sparse in the representation of the Scopus data; the secondary documents (e.g., editorials in Current Contents) not processed in Scopus, but included in WoS enrich the representation. Furthermore, HistCite™ has an option to export the citation network as a Pajek file that can be read by most network analysis and visualization programs. Garfield’s texts are centered by him as a personality and entrepreneur in different domains more than intellectually, although there are a number of recurring themes. Our own main paths are shaped along a line along which components indicate longer-term projects.