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RESEARCH GUIDES

Bibliometrics and Altmetrics: Measuring the Impact of Knowledge

This guide includes information on which of the databases contain citation measures that can be used to gage either an author, article or journal impact.

Getting Started

Browse the top 100 publications in several languages, ordered by their 5-year h-index and h-median metrics.

Limit your search...

  1. To see which articles in a publication were cited the most and who cited them. Click on its h-index number to view the articles as well as the citations underlying the metrics (highlighted in yellow with a blue box/arrow).
  2. To explore publications in research areas of your interest. Select one of the areas in the left column (outlined with a green box and a green arrow).
  3. To browse by research area. It's available only for English publications. You can search for specific publications in all languages by words in their titles (red box/arrow).

Browse the top Articles from the top 100 publications

In publishing the h5 index for their Top 100 publications in Google Scholar Metrics, the top articles cited are also included. When viewing the Top 100 publications, click on the h5 index score to see the most highly cited articles from that journal (h5-core). Then, you can click on the citation count for any article in the h5-core to see who cited it.

This disclaimer accompanies the top articles cited: "Dates and citation counts are estimated and are determined automatically by a computer program."

Available Metrics

Google Scholar has adapted the h-index method of impact for publications and an h5 variation for five complete calendar years.

From Google Scholar:

"The h-index of a publication is the largest number h such that at least h articles in that publication were cited at least h times each. For example, a publication with five articles cited by, respectively, 17, 9, 6, 3, and 2, has the h-index of 3.

The h-core of a publication is a set of top cited h articles from the publication. These are the articles that the h-index is based on. For example, the publication above has the h-core with three articles, those cited by 17, 9, and 6.

The h-median of a publication is the median of the citation counts in its h-core. For example, the h-median of the publication above is 9. The h-median is a measure of the distribution of citations to the articles in the h-core.

The h5-index, h5-core, and h5-median of a publication are, respectively, the h-index, h-core, and h-median of only those of its articles that were published in the last five complete calendar years."

Coverage of Publications

From Google Scholar:

"Scholar Metrics currently cover articles published between 2009 and 2013, both inclusive. The metrics are based on citations from all articles that were indexed in Google Scholar in June 2014. This also includes citations from articles that are not themselves covered by Scholar Metrics.

Since Google Scholar indexes articles from a large number of websites, we can't always tell in which journal a particular article has been published. To avoid misidentification of publications, we have included only the following items:

    • journal articles from websites that follow our inclusion guidelines;
    • selected conference articles in Computer Science and Electrical Engineering;
    • preprints from arXiv, SSRN, NBER and RePEC - for these sites, we compute metrics for individual collections, e.g., "arXiv Superconductivity (cond-mat.supr-con)" or "CEPR Discussion Papers".

Furthermore, we have specifically excluded the following items:

    • court opinions, patents, books, and dissertations;
    • publications with fewer than 100 articles published between 2009 and 2013;
    • publications that received no citations to articles published between 2009 and 2013.

Overall, Scholar Metrics cover a substantial fraction of scholarly articles published in the last five years. However, they don't currently cover a large number of articles from smaller publications."