Web of Science indexes 20 000 journals – there’s a new way to work out what research fits where

Data analytics provider Clarivate has a created a citation-based classification system, developed with the Centre for Science and Technology Studies at Leiden University (source of the wonkiest of research rankings).

Journals now indexed in Web of Science are grouped in 254 categories. Every item in each journal is allocated to a  category by expert-input.

But the new approach uses a categorical system based system, with articles and review collected into larger units, based on underlying data.  

Clarivate  states, “it is intended to exploit the advantages claimed for article-level algorithmic classification.” It’s called “Citation Topics,” – the classification system is built from the citation network.

The existing version, (as of December) sorts more than 50 million documents into 2444, 326 and ten topic layers. Clarivate mapped where content sits when located by “bottom-up” citation clustering and “top-down” journal categorising to find classification groups, “align across the landscape.”

“This suggests that a ‘natural order’ is underpinning the guiding principles inherent in both expert judgment and citation linkage,” Clarivate claims.

So why bother?  Because it seems categorising by metadata delivers benefits using human concepts does not. “A citation-based classification of articles and reviews progressively links individual elements into larger units with shared characteristics based on features in the underlying data. …. It also gives opportunity for novel groups to appear that were not previously possible with journal-based schemes.”