Author-level metrics measure the scholarly impact of an individual researcher’s
Author-level metrics measure the scholarly impact of an individual researcher’s publication output. They include publication output, citations to the researcher’s publications and h-index. Some article-level metrics can be used at an author level, usually by calculating the average for that metric across an author’s publication output.
The h-index is one most well known author-level metrics is the h-index. It is calculated by counting the number of publications for which an author has been cited at least that same number of time. It attempts to measure a researcher’s productivity and impact. An author’s h-index can be easily found on their profile pages in tools such as Google Scholar, Scopus and Publons. Read the h-index page on the Metrics Toolkit website to find more information about the h-index, including appropriate and inappropriate use cases and limitations.
The h5-index is the h-index, calculated using a 5-year publication window.
The g-index gives more weight to highly-cited publications. See Wikipedia for an explanation of how it is calculate.
The i10-index the number of publications with at least 10 citations
Exercise: Go to Google Scholar and search for a researcher at your institution and click on Google Scholar Citations profile. What is their h-index?
Journal-level metrics
Journal-level metrics aim to quantify the reach, impact and prestige of a journal. There are a number of journal-level metrics, including Journal Impact Factor (JIF), Scimago Journal Rank (SJR), CiteScore and Source Normalized Impact per Paper (SNIP). Journal-level metrics are the basis for a number of journal rankings, as described below.
The Journal Impact Factor (JIF) is a Clarivate Web of Science metric and in Journal Citation Reports (JCR), a subscription-based database. A journal’s impact factor is calculated by dividing the number of times articles were cited by the number of citable articles in a journal for a two-year period. Journals in JCR are allocated to different subject categories and allocated to quartiles within the category.
Scimago Journal Rank (SJR) is another journal-level metric and expresses the average number of weighted citations received in a selected year by the documents published in that journal in the previous three years. Scimago Journal Rank is based on Scopus data. Journals are allocated to different subject categories and allocated to quartiles within the category.
Source Normalized Impact per Paper is a metric developed by CWTS. It is calculated as the number of citations given in the present year to publications in the past three years divided by the total number of publications in the past three years. Citations are normalised to account for differences in citing behaviour in different disciplines. It is based on Scopus data. Journals are allocated to different subject categories.
CitesScore is calculated by dividing the number of citations to documents (articles, reviews, conference papers, book chapters, and data papers) by