The Leiden Ranking

The Leiden ranking for 2013 is out. This is produced by the Centre for Science and Technology Studies (CWTS) at Leiden University and represents pretty much the state of the art in assessing research publications and citations.

A variety of indicators are presented with several different settings but no overall winner is declared which means that these rankings are not going to get the publicity given to QS and Times Higher Education.

Here are top universities, using the default settings provided by CWTS.

Total Publications: Harvard
Citations per Paper: MIT
Normalised Citations per Paper: MIT
Quality of Publications: MIT

There are also indicators for international and industrial collaboration that I hope to discuss later.

It is also noticeable that high flyers in the Times Higher Education citations indicator, Alexandria University, Moscow Engineering Physics Institute (MEPhI), Hong Kong Baptist University, Royal Holloway, do not figure at all in the Leiden Ranking. What happened to them?

How could MEPhI, equal first in the world for research influence according to THE and Thomson Reuters, fail to even show up in the normalised citation indicator in the Leiden Ranking?

Firstly, Leiden have collected data for the top 500 universities in the world according to number of publications in the Web of Science. That would have been sufficient to keep these institutions out of the rankings.

In addition, Leiden use fractionalised counting as a default setting so that the impact of mutiple-author publications is divided by the number of university addresses. This would drastically reduce the impact of publications like the Review of Particle Physics.

Also, by field Leiden mean five broad subject groups whereas Thomson Reuters appears to use a larger number (21 if they use the same system as they do for highly cited researchers.) There is accordingly more chance of anomalous cases having a great influence in the THE rankings.

THE and Thomson Reuters would do well to look at the multi-authored, and most probably soon to be multi-cited, papers that were published in 2012 and look at the universities that could do well in 2014 if the methodology remains unchanged.