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Guides & Tutorial, Pao-yue Kong Library, The Polytechnic University of Hong Kong

Research Visibility: Author Impact

What is h-index?

h-index or Hirsch index was proposed in 2005 by Jorge E. Hirsch to quantify the research achievement of physicists based on their publication record. The number attempts to measure both the productivity and citation impact of the publications of a scientist or scholar.

The diagram below shows a researcher with an index of h. Out of all his publications, h publications have at least h citations each.

An h-index of 20 means that, out of all papers published by an author, 20 of them have been cited at least 20 times

Remarks on using h-index

  Different databases have different content coverage and this will have an impact on the results, for example, the h-index of an author may be different in Scopus, Web of Science and Google Scholar.

  The value of h-index from Google Scholar may be higher than Scopus and Web of Science because Google Scholar has larger content coverage and looser inclusion criteria.

  Citation practices vary across disciplines; it is not advisable to compare the h-index of scholars in different disciplines.

  The h-index may vary depending on how long the scholar has been publishing and on the number of articles they’ve published. Older scholars will tend to have a higher h-index than younger scholars based on the fact that the former group have more publications. 

  If you find it difficult to locate all your publications in Web of Science, creating a ResearcherID profile and adding all your publications from Web of Science will help you accurately track your citation counts and h-index. To populate your profile in ResearcherID, read Research Visibility: Researcher ID for details.

Online Tutorial

An online tutorial (6:08) which shows the way to generate Citation Report in Web of Science and introduces the concept of h-index.

Overview

There are a few ways to measure an author's impact:

  • Document Counts - the number of publications an author has authored
  • Citation Counts - the number of times an author’s publications are being cited by other researchers
  • h-index - an index to measure both the productivity and impact of the published work of an author/a researcher
  • i10-index - the number of publications with at least 10 citations

Document Counts, Citation Counts and h-index are available in Web of Science, Scopus and Google Scholar while i10-index is only available in Google Scholar.

This guide outlines:

  1. What is h-index?
  2. Find Document Counts, Citation Counts and h-index in Scopus
  3. Find Document Counts, Citation Counts and h-index in Web of Science
  4. Find Author Metrics in Google Scholar
  5. Remarks on using h-index

Find Document Counts, Citation Counts and h-index in Scopus

This box shows document counts, citation counts and h-index of an author in Scopus.

► Step 1. Go to Scopus.

► Step 2. Conduct an Author Search.


► Step 3. Select relevant author profile(s).


► Step 4. View the author's h-index and citation counts from Citation overview.

Find Document Counts, Citation Counts and h-index in Web of Science

This box shows the steps to find document counts, citation counts and h-index of an author by creating a citation report in Web of Science.

► Step 1. Go to Web of Science.

► Step 2. Conduct an Author Search.


► Step 3. Select Research Domain(s) of the author.


► Step 4. Select Affiliation(s) associated with the author.


► Step 5. Select the Work(s) which belongs to the author.


► Step 6: View the author's h-index and citation counts from Citation Report.

Find Author Metrics in Google Scholar

To locate an author's metrics in Google Scholar, simply search the author's name using Google Scholar. The metrics will only be available for authors who have set up their Google Scholar profile with publications (in public view).

i10-index is the number of publications with at least 10 citations. It can be calculated against all publications for an author, or a 'recent' version (e.g. "Since 2012"), which is the number of publications that have received at least 10 new citations in the past 5 year.