Garfield's Law of Concentration
Garfield's Law of Concentration is the bibliometric principle that the bulk of the significant scientific literature is concentrated in a relatively small, largely multidisciplinary core of journals. Formulated by Eugene Garfield — founder of the Science Citation Index — and presented in his 1972 Science paper 'Citation analysis as a tool in journal evaluation', the law observes that when journals are ranked by how often they are cited, a core of perhaps 500 to 1,000 journals accounts for the overwhelming majority of all citations across all fields. Garfield framed it as a generalization and corollary of Bradford's earlier law of scattering: the long tail of any one discipline's literature is in large part composed of the cores of other disciplines, so a single multidisciplinary core covers science as a whole. The law underpins the rationale for selective, citation-based journal indexing.
Rekodi ya chanzo
Nukuu zimehamishwa kwa uhalisi kutoka kwa rekodi ya chanzo cha mbinu. Hakuna uthibitisho wa kiwango cha dai unaodokezwa kutoka kwao.
- Garfield, E. (1972). Citation analysis as a tool in journal evaluation. Science, 178(4060), 471-479. · DOI 10.1126/science.178.4060.471
- Bradford, S. C. (1934). Sources of information on specific subjects. Engineering: An Illustrated Weekly Journal, 137, 85-86. · URL
Madai yaliyotunzwa
Madai yamehifadhiwa katika daftari la ushahidi, kila moja ikiwa na tathmini yake.
Mwonekano huu haubuni tathmini ya dai wakati daftari haina yoyote.
Mbinu zinazohusiana
Zilizotengenezwa kutoka kwa grafu ya mbinu na kuonyeshwa kama uhusiano uliopendekezwa na mashine — hakuna dai la ushahidi linalodokezwa.