Bibliometrics are one of the ways to quantify research impact. It is the analysis of bibliographic data, including citation analysis.
Article-level metrics refer to citation counts (or altmetrics, which is discussed on the next page). This is the number of times an article is cited and is reported in numerous indexes (for example, Scopus, Web of Science, Google Scholar). The same article can have varying levels of citations reported due to indexing differences between platforms.
The term h-index was coined in 2005 by J. E. Hirsch. In this measure, h refers to the number of publications a researcher has with ≥ h citations. For example, a researcher with at least ten journal articles that had all been cited at least ten times would have an h-index of ten.
This metric can be found as part of a researcher's profile in Google Scholar, Scopus, and Web of Science.
The i10-index was introduced by Google Scholar in 2011 (and is only reported in Google Scholar). It refers to the number of publications an author has that have at least ten citations.
This metric can be found as part of a researcher's profile in Google Scholar.
The field-weighted citation impact (FWCI) is a ratio of the total citations an author has received over the total citations expected, based on the author's research field. This is a normalized value that allows for comparison between fields with different expectations of publishing. An FWCI of 1 would mean that an author's citations are equal to the average of the field. If the FWCI more than one, the author has received more citations than what is expected for their field.
This metric can be found as part of a researcher's profile in Scopus.
An author's impact beamplot is a visual representation of their publication percentile.
This metric can be found as part of a researcher's profile in Web of Science.
The g-index was first introduced by L. Egghe in 2006. It was proposed as an alternative to the h-index as the g-index gives more weight to more frequently cited papers. Egghe defined it as "a set of papers has a g-index g if g is the highest rank such that the top g papers have, together, at least g2 citations. This also means that the top g + 1 papers have less than (g + 1)2 papers" (Egghe, 2006).
Journal impact factor is a ratio of the number of times the current year's articles have been cited over the number of articles published in the last two years. This metric allows for fair comparison between journals of different ages. It is published by Clarivate and is included in the Web of Science Core Collection.
For example, here is the journal impact factor for the Asian Journal of Social Psychology, available on Web of Science.
The SCImago Journal Rank (SJR) is publicly available, though its data comes from the Scopus database. It ranks journals based on prestige and groups them based on subject area, subject category, and country.
For example, here is the journal impact factor for the Asian Journal of Social Psychology, available on Scopus.
A journal's CiteScore is the ratio of the average number of citations in a year to the number of recently published articles. It is published by Scopus.
For example, here is the CiteScore for the Asian Journal of Social Psychology, available on Scopus.
Using the last 5 years of published content, the Eigenfactor Score reflects the density of the network of citations around a journal during the current year. Both the number of citations and the source of citations are considers; highly cited sources will have a stronger influence on the network that less cited sources. It's calculation doesn't include journal self-citations. It is published by Clarivate and is included in the Journal Citation Reports.
For example, here is the Eigenfactor Score for the Asian Journal of Social Psychology, available on Journal Citation Reports.
There are limitations to bibliometrics.
