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Research Impact


Research is a very complex process. Performance is influenced by many factors such as a researcher’s age, position or research domain. Therefore it is extremely difficult to “measure” the impact of an individual researcher or a research group on the discipline or society.

However, bibliometrics can supplement evaluation and can provide useful information on the impact of a publication. The number of citations can be an indicator on how well received and discussed published research is.

Wolfgang Glänzel (Univ. Leuven) and Paul Wouters (Univ. Leiden) recently introduced the “Do’s and Don’ts in Individual-Level Bibliometrics”.

Keeping track of your research

You can do seveal things to find out when and by whom your publication is cited:

  • Set up citation alerts for your publications in Web of Science and Scopus
  • Create a profile in Google Scholar Citations and get citation alerts
  • Sign up on social networking sites, list your publications there and track how often they have been viewed and who is following you.
  • Use alternative metrics (Altmetrics) to track the impact of your research. Downloads, tweets, likes or mentions are indicators on how often you publication has been discussed. Create an account with ImpactStory or install the bookmarklet

How to improve your impact

The number of publications in any field increases enormously every year. It becomes more and more difficult for a researcher to keep track of recent publications even in relatively well defined disciplines. That means that it becomes more important to make a publication more visible so it won’t be overlooked.

A few easy to do and easily applied steps can raise the visibility of your publication:

  • Always use the same name version consistently throughout your career, e.g. “John J. O’Sullivan”, NOT “J. J. O’Sullivan”, “John O’Sullivan”, “John James O’Sullivan”
  • Use a standardised institutional affiliation and address
  • Publish in journals with high impact factor
  • Collaborate with researchers in other institutions
  • Deposit your publication (final draft or published paper - depending on copyright policy of publisher) in the Koc University Institutional repository. This has the added advantage of being able to automatically populate your School’s publications listing via RSS
  • Take advantage of SEO (search engine optimisation) by carefully selecting title and keywords for your publication
  • Register for an ORCID and/or Researcher ID in order to be more easily found in databases
  • Present preliminary research findings at meetings and conferences
  • Join academic social networking sites, e.g., ResearchGate, LinkedIn
  • Utilise social bookmarking with Mendeley, Zotero or CiteULike
  • Start a blog devoted to your research project
  • Consider communicating information about your research via Twitter


The h-index (a.k.a. Hirsch index) is a combined measure of both productivity and impact. An index of h means that your h most highly-cited articles have at least h citations each, e.g. a researcher's h-index will be 5 if 5 of his/her articles have been cited at least 5 times.


The h-index is more informative than total number of articles (which ignores how well those articles have been received by other researchers) or total number of citations (which can be inordinately influenced by a small number of highly-cited articles and therefore not an accurate reflection of productivity).
The h-index can be calculated by using the following tools:

There are a number of limitations and cautions to be taken into account when using the h-index. These include:

  • Academic disciplines differ in the average number of references per paper and the average number of papers published by each author
  • The length of the academic career will impact the number of papers published and the amount of time papers have had to be cited. The h-index is therefore a less appropriate measure for junior academics.
  • There are different patterns of co-authorship in different disciplines.
  • Individual highly cited papers may not be accurately reflected in an h-index.

Alternative indices

hi-index If multiple-authored articles are common within your discipline, your h-index may be relatively high. Your degree of contribution to each article, however, may be thought to diminish as your number of co-authors increases. The hi-index (aka individual h-index) takes the number of co-authors into account. Your hi-index is equal to your h-index divided by the average number of authors on the articles in your h core.

g-index One of the strengths of the h-index—its insensitivity to highly-cited papers—could also be considered a weakness. That is, once an article has a sufficient number of citations to gain inclusion into the h core, additional citations are irrelevant. The g-index, in contrast, weights highly-cited papers more heavily. An index of g means that your g most highly-cited articles together have at least g-squared citations. Your g-index will always be equal to or greater than your h-index. 

m-index If your have been publishing for decades, your h-index will be higher than a researcher who has been pusblishing for only a few years. The m-index takes differences in career length into account, by dividing your h-index by the number of years that you have been publishing.

hc-index If you published a few highly-cited papers decades ago but are now inactive, your h-index may be higher than an established researcher who steadily continues to publish or a promising new researcher who is just beginning to gain recognition. The hc-index (AKA contemporary h-index) weights newer articles more heavily than older articles, so that articles lose their value over time. This allows a clearer picture of more recent levels of productivity and impact.

Several other alternative indices have also been proposed.