What impact can be measured?
H-index (Hirsch-index) measures and compares researchers´ scientific publication output.
Citation databases contain citation information and the linkages between citing articles - who has cited which article - and enable the calculation each researcher´s h-index.
How to calculate H-index
Typical of H-index
Citation databases Web of Science, Scopus and Google Scholar have each their own h-indexes. Google Scholar´s h-index counts non-scientific publications like master's theses, too. Furthermore, part of the publications are duplicates because of self-archiving. Google Scholar´s h-index differs significantly from those of WoS and Scopus.
h-index quick guides
An index of g means that your g most highly-cited articles together have at least g-squared citations.
Typical of G-index
The citation report (WoS) / overview (Scopus) provides aggregate citation statistics like:
Publication Forum (in Finnish often referred to as JUFO) evaluates Finnish and foreign academic publication channels. Publication Forum operates under the auspices of the Federation of Finnish Learned Societies (TSV).
Publication Forum ratings
The three-level classification rates the major foreign and Finnish publication channels of all disciplines.
Journal Citation Reports is a part of the Web of Science database which tells the journal impact factors (JIF).
Impact Factor score
SJR, SNIP and CiteScore can be seen in the context of Scopus journals (Sources - Browse sources). You can compare sources.
SJR indicator (SCImago Journal Rank)
SNIP indicator (Source Normalized Impact per Paper)
How to calculate CiteScore
A journal has an h-index of h if there are at least h papers published in that journal that have received at least h citations each.
Typical of journal h-index...
Journal Citation Reports also publishes Article Influence scores and Eigenfactor scores.
Article Influence (AI) score
Eigenfactor (EF) score