Increasingly metrics are being used as a measure of research impact or research influence of an individual scientist or group. Metrics must always be considered in context (citation patterns vary in different disciplines) and should never be used as the only measure. When used in conjunction with peer review some metrics are quite robust.

You can use metrics to illustrate your track record when applying for grants and promotion. If it is difficult to search for your publications (other authors share your name and initials; or inconsistent use of your name and initials, or mistakes in the database records) it may be useful to use ResearcherID.

Different types of metrics commonly used

• Citation metrics – the statistical analyses of citation counts
• Bibliometrics – broader term includes publication counts, citation analyses and content analyses
• Webometrics – includes download counts and number and type of hyperlinks

Let's make science metrics more scientific Nature 464, 488-489 (25 March 2010) doi:10.1038/464488a; Published online 24 March 2010.

Citation metrics, the statistical analyses of citation counts, have found widespread application in the research community in the area of research evaluation. They are being used to infer quality or academic impact at the level of an individual article, a journal, an individual researcher, as well as aggregated to infer quality at the research group, discipline, organisational unit within an institution, institution and country level.

For an individual article, the number of times it has been cited by other articles is generally considered to be indicative of the article’s academic impact, with the assumption being that research articles of high academic quality are likely to be cited more often than those of lesser quality. Other metrics, including secondary citations (the number of citations received by the articles citing the article) have also emerged.

For an individual researcher, the following are the most common citation metrics in use:

• Career citation count
• Career citation count with self-citations removed
• Citations per paper
• h-index (Hirsch index)
• For selected articles: total citations, citations per paper etc.

To profile a research group, the measures which are typically used include the total number of publications in a given timeframe (e.g. last 5 years) , the total citation counts (for the publications within the timeframe), and the ratio of these two, the citations per paper. Recently, the h-index has also been applied to entities such as research groups, although the index was developed and introduced as an indicator for an individual researcher.

To profile a large group of researchers across many disciplines, a more detailed analysis of their research outputs would consider the measures mentioned above (total number of publications in a given timeframe, the total citation counts (for the publications within the timeframe), and the ratio of these two, the citations per paper) disaggregated at the discipline level.

Other citation metrics consider the analysis of the citations by journal, country or institution etc.

More information

Understanding and Finding Citation Metrics June 2008. American Museum of Natural History.

Good definitions of different citation metrics (Some Untested Citation Metrics) SPIRES, SLAC National Accelerator Laboratory, Operated by Stanford University for the U.S. Dept. of Energy.

Bibliometrics is a discipline in its own right with a much broader scope than is described by the term citation metrics. It includes publication counts, citation analyses and content analyses. However, the term bibliometrics is often used in contexts where citation metrics may be more appropriate.

Definitions of bibliometrics on the web:

• Bibliometrics is a set of methods used to study or measure texts and information. Citation analysis and content analysis are commonly used bibliometric methods... Wikipedia
• The statistical analysis of texts, especially of published literature Wiktionary
• bibliometric - Of or pertaining to bibliometrics Wiktionary
• is the application of statistical or mathematical methods to groups of bibliographic references (for example, authorship, publications, literature ... Quantum 3 the solutions people

More information

• Frequently asked questions on Bibliometrics from Elsevier
• What is Bibliometrics and Scientometrics? JISC
• Statistical Bibliography from Author Cocitation Analysis By Sean B. Eom
• Using bibliometrics white paper by Thomsom Reuters

Given the rapid expansion of the internet over the past decade, there are emerging measures of impact and influence that are finding application in the research evaluation area based on the use of information in cyberspace. The terms used to describe this field of scientometrics include cybermetrics and webometrics. The measures include things like download counts and site hits as well as links analysis and web citation analysis.

The article Bibliometrics to webometrics in the Journal of Information Science provides a informative review of webometrics, which it describes as "a modern, fast-growing offshoot of bibliometrics".

The use of these emerging metrics in research evaluation is subject to ongoing debate, with some of these issues discussed in the paper Validating research performance metrics against peer ranking, Stevan Harnad, Ethics in Science and Environmental Politics, Vol.8, 103-107, 2008.

The Webometrics Ranking of World Universities has been developed by the Cybermetrics Lab, a research group belonging to the Consejo Superior de Investigaciones Cientificas (CSIC), the largest public research body in Spain. This ranking makes use of a number of webometric measures. In the July 2009 Webometric World rankings, UQ is ranked 109 globally and 2nd in Oceania in these rankings.

From Scholarship 2.0: An Idea Whose Time Has Come The blog Scholarship 2.0 is devoted to describing and documenting the forms, facets, and features of alternative Web-based scholarly publishing philosophies and practices. The variety of old and new metrics available for assessing the impact, significance, and value of Web-based scholarship is of particular interest.

Neylon C, Wu S (2009) Article-Level Metrics and the Evolution of Scientific Impact. PLoS Biol 7(11): e1000242. doi:10.1371/journal.pbio.1000242 / Published: November 17, 2009. Published also through Scholarship 2.0, Wednesday, November 18, 2009.

National and Institutional Perspectives on Metrics-Based Research Evaluation
Brisbane, 16 and 17 April 2009. Conference Jointly Organised By: Thomson Reuters and The University of Queensland
Conference papers and presentations

ISSI 2009 - 12th International Conference on Scientometrics and Informetrics
under the auspices of the International Society for Scientometrics and Informetrics (ISSI)
July 2009, in Rio de Janeiro, Brazil.