Alternative metrics (altmetrics): These are public engagement indicators that measure interactions with publications in non-scholarly venues like blogs, tweets, article downloads, and shares.
Article Indicators: Indicators that provide insight into the citation impact of a particular article. Some article indicators are field-normalized which allow the indicator to be compared across disciplines.
Bibliometrics: The statistical analysis of publication and citation counts, and other bibliographic data (e.g., journal, author affiliation). It is often used to assess the productivity and "impact" of entities (individual authors, groups, universities), as well as the dissemination and use of information among countries, disciplines, and groups of individuals.
Citation Count or Number of Citations: A count of the number of times an article, or set of articles, has been cited by other researchers.
Eigenfactor Score: This calculation is based on the rate that a journal's articles (published within five years) have been cited in the current year. It gives more weight to citations from highly cited journals than citations from lesser cited journals.
Field Citation Ratio (FCR): A citation-based measure of scientific influence of one or more articles. It is calculated by dividing the number of citations a paper has received by the average number received by documents published in the same year and in the same Fields of Research (FoR) category.
Field-Weighted Citation Impact: This article-level calculation is the ratio of the total citations actually received by the denominator’s output, and the total citations that would be expected based on the average of the subject field.
h-index: A measure that attempts to describe an author’s productivity and impact. An author's h-index is represented by the number of papers (h) with a citation number ≥ h. For example, a scientist with an h-index of 14 has published numerous papers, 14 of which have been cited at least 14 times.
Journal Impact Factor (IF): This indicator measures the average citation frequency of a journal's articles within a particular year. The calculation is based on a two-year period, where a journal's citations are divided by the number of total published citable articles.
Journal indicators: Measures that journals use to illustrate the ratio of citations received per article published. Many see this as indicative of a journal's prestige.
ORCID: An ORCID (Open Researcher and Contributor ID) number enables transparent and trustworthy connections between researchers, their contributions, and affiliations by being an identifier for individuals to use with their name as they engage in research, scholarship, and innovation activities.
Relative Citation Ratio: This article-level calculation uses an article's co-citation network to field- and time-normalize the number of citations received.
SCImago Journal Rank (SJR): This calculation weighs each incoming citation to a journal by the SJR of the citing journal, with a citation from a high-SJR source counting for more than a citation from a low-SJR source.
Source Normalized Impact per Paper (SNIP): This calculation is a sophisticated metric that intrinsically accounts for field-specific differences in citation practices. It does so by comparing each journal’s citations per publication with the citation potential of its field, defined as the set of publications citing that journal.