User:Rajukomalla000/sandbox

Bold textBold text

The Science Citation Index (SCI®) was first promulgated in Science in 1955, as an up-to-date tool to facilitate the dissemination and retrieval of scientific literature [3]. Its practical realization was possible thanks to the already-existing information service, Current Contents. The early computer had made it feasible for Current Contents to appear each week together with its title word indexes and author address directory. In those days, conventional indexes were anywhere from six months to three years behind the literature. Nevertheless, the SCI’s success did not stem from its primary function as a search engine, but from its use as an instrument for measuring scientific productivity, made possible by the advent of its by-product, the SCI Journal Citation Reports (JCR) and its Impact Factor rankings. Citation analysis has blossomed over the past three decades into the field of scientometrics, already possessing a specialized journal which started in 1978, Scientometrics, and its own International Society of Scientometrics and Informetrics (ISSI). Over 15 years ago, SteveBold text Lock aptly named the application of scientometrics to journal evaluation “journalology” [10]. All citation studies should be normalized to take intoJournal Citation Reports account variables such as discipline, half-life, and citation density [12]. The half-life (number of retrospective years required to find 50% of the cited references) is longer for a physiology journal than that for a physics journal. For some fields, JCR’s two-year based impact factors may or may not give as complete a picture as would a five- or ten-year period. Nevertheless, when journals are studied within disciplinary categories, the rankings based on 1-, 7- or 15-year impact factors do not differ significantly [6,7]. The citation density is the average number of references cited per source article. Citation density (R/S) is significantly lower for mathematics journals than for molecular biology journals. There is a widespread but mistaken belief that the size of the scientific community that a journal serves significantly affects the journal’s impact factor. This assumption overlooks the fact that while most authors produce more citations, these must be shared by a larger number of cited articles. Most articles in most fieldsItalic text