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CMU-Africa: Citation Analysis

An introductory guide for students and faculty on our Rwanda campus.


The “h-index” was introduced in 2005 by the American physicist, Professor Jorge Hirsch in his article “An index to quantify an individual’s scientific research output as a mean to measure both the scientific productivity and the apparent scientific impact of a scientist.

The H-index is relatively effective in comparing researchers working in the same scientific field, and not comparable across disciplines due to different publishing and citation patterns.

How to calculate h-index?

The h-index is based on a list of publications ranked in descending order by the Times Cited. The value of h is equal to the number of papers (N) in the list that have N or more citations.

Ex. An h-index of 10 means that there are ten papers that have ten or more citations.

Where to find h-index calculated

Calculated automatically in subscription-based databases

Each database is likely to produce a different h for the same scholar, because of different coverage.

Access Web of Science
Enter scientist's name in the author search box
Add limits (field, year, affiliation, etc) to get results for the right person
Click on Search 
Click on Citation Report on the right hand corner of the results page – the h-index is on the right of the screen

NOTE. Web of Knowledge was found to have strong coverage of journal publications, but poor coverage of high impact conferences.

  • Scopus

For nonsubscribers, the publisher of Scopus, Elsevier, provide Scopus Preview: Author Free Lookup, that gives the author's h-index (calculated from 1996 data to the present only), and the number of times this individual was cited in the Scopus database (you cannot see which of the author's articles are being cited, nor which articles are doing the citing). 


Manually calculated in databases that provide citation information


In the case of disciplines not well represented in Web of Science or Scopus, h-index can still be calculated by manually counting the citations. Some databases that offer citation counts are:  

Free tools to calculate h-index

  • Publish or Perish - freeware software that retrieves and analyzes academic citations. It uses Google Scholar to obtain the raw citations.
  • Scholar H-Index Calculator - Add-ons for Firefox. This addon will automatically display some of the most known citation indices (h-index, g-index, e-index) for any author (or any arbitrary query regarding journals, keywords, etc.), when querying on Google Scholar.

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