The term author-related indicators covers all indicators that exclusively attempt to quantify the scientific work of individuals. These can help answer the following questions, for example:

• How many publications have I published as an author in a certain period of time?

• How often have I been cited?

• How can the scope and influence of my scientific findings be increased or strengthened?

Some author-related indicators are explained below.

Number of publications

Represents the absolute number of published documents in a defined time window.

Number of citations

Represents the absolute number of citations of defined publications in a defined time window.

Citation rate

The citation rate measures the number of citations in relation to the number of publications. It thus indicates how often a person's article is cited on average. Any publications that are outliers are heavily weighted here.

h-index

The h-index, also known as the Hirsch index, represents a ratio between the number of publications, usually of a person, and their citations. The h-index of a person can be at most as large as the number of publications of the person, but only if these were cited in each case at least as often as the total number of publications. For example, if a person has two publications cited twice each, the person's h-index is 2. If both publications are cited three times each, the index remains at two. Only after a third publication and at least three citations of each of the three publications does the h-index increase to 3. The higher the h-index of a person, the greater the number of frequently cited publications of this person. Therefore, once an h-index is reached, it remains at least the same, but cannot increase by further publications alone. Moreover, individual outlier publications that are cited more or less frequently do not carry much weight. The h-index is mostly applied to individuals, but can also be applied to groups of individuals, facilities, and institutions. The h-index is criticized as not sufficiently meaningful because it measures productivity instead of quality. Moreover, it can vary depending on the data base on which it is measured.

Field-Weighted Citation Impact (FWCI)

This indicator is used for both individual publications and authors and takes into account discipline-specific publication cultures. FWCI is the ratio between the actual number of citations a publication has received to date and the expected number for a publication with similar characteristics. The expected number refers to the average number of citations over the past three years for all issues of the same age, document type, and discipline. The FWCI was introduced by Elsevier's Scopus database (see below).