Garfield's law

The Garfieldsche law (according to Eugene Garfield ) states that the same number of citations of articles from journals in a specified field of science three groups of journals distributed. There is a core, a middle and a marginal zone of journals, individual journals switch between these groups, but the approximate proportion of 1: 4: 16 remains.

If one looks at the journals of a single scientific field and examines the citation behavior there, one notices that a third of the citations are from very few journals (less than 5% of the journals).

There are three sets of journals, the core, middle and edge zones, which should be in a ratio of 1: 4: 16, with the same number of citations in each zone.

Examples

Example: Philosophy (three-zone classification like Bradford )

given: 735 references (born 1975); Journals cited therein: 223

Core: 6 journals (named in 245 citations)

Middle: 23 journals (named in 245 citations)

Margin: 194 journals (named in 245 citations)

so: 6: 23: 194 = 1: 3.8: 32.3 ~ 1: 4: 32 (expected: 1: 4: 16),

therefore: very large peripheral zone

Garfield drafted his law with the journals represented in the ISI ( Institute for Scientific Information ).

Applications

Eugene Garfield is the developer of the Science Citation Index . In doing so, he examined the distribution of the references to the individual journals in a field and recognized the validity of his law on the distribution of citations in scientific journals.

From this he deduced the Garfieldian concentration: 75% of all citations come from almost 1,000 journals; 84% of all citations are from around 2,000 journals;

The practical consequence for his ISI database Web of Science was: A database that evaluates several thousand journals (namely the most frequently cited ones) produces a representative image of science; The source selection for Science Citation Index is based on this .

In general, the affiliation of a journal to a zone can change over time, so that the ISI ( Information Sciences Institute ) also regularly checks and accepts new journals and removes old journals.

literature

Eugene Garfield: The mystery of the transposed journal list - wherein Bradford's law of scattering is generalized according to Garfield's law of concentration. In: E. Garfield: Essays of an Information Scientist . Vol 1. ISI Press, Philadelphia 1977, pp. 222-223.