Compara mètodes

	Journal Self-Citation Analysis	Immediacy Index
Camp	Bibliometria	Bibliometria
Família	Process / pipeline	Process / pipeline
Any d'origen	1999	1972
Autor original	Wolfgang Glanzel et al.; Ronald Rousseau	Eugene Garfield (ISI / Journal Citation Reports)
Tipus	Self-citation decomposition pipeline	Same-year citation-rate pipeline
Font seminal	Glanzel, W., Debackere, K., Thijs, B., & Schubert, A. (2006). A concise review on the role of author self-citations in information science, bibliometrics and science policy. Scientometrics, 67(2), 263-277.	Garfield, E. (1972). Citation analysis as a tool in journal evaluation. Science, 178(4060), 471-479.
Àlies	Self-Citation Rate Analysis, Journal Self-Referencing Analysis, Self-Citing and Self-Cited Rates, Citation Manipulation Detection	Journal Immediacy Index, Same-Year Citation Rate, Current Citation Rate, Year-of-Publication Citation Index
Relacionats	3	3
Resum	Journal self-citation analysis separates the citations a journal gives to itself from the citations it gives to and receives from the wider literature, in order to understand a journal's internal coherence and to detect potential inflation of impact metrics. Ronald Rousseau showed in 1999 that a journal's citation curve is really two curves superimposed: a self-citation component and an external-citation component, each with its own timing. Wolfgang Glänzel and colleagues, surveying the self-citation literature, distinguished the legitimate, communicative role of self-citation from its problematic use to manipulate indicators, and clarified how to measure its effect. The analysis revolves around two complementary rates: the self-cited rate, the share of a journal's incoming citations that come from itself, and the self-citing rate, the share of its outgoing references that point to itself. Comparing impact metrics with and without self-citations reveals how much a journal's standing depends on citing itself.	The Immediacy Index measures how quickly a journal's articles are cited by counting the citations they receive in the very year they are published. Eugene Garfield, who created the Science Citation Index and the impact factor, introduced the immediacy index as part of the Institute for Scientific Information's journal-evaluation methodology and described it in his landmark 1972 Science paper on citation analysis as a tool in journal evaluation. While the impact factor averages citations over a two-year window, the immediacy index uses a zero-year window: it divides the citations made in a given year to that year's articles by the number of citable items published that year. A high immediacy index means a journal's work is picked up almost immediately, the signature of a fast-moving, frontier field or of journals that publish hot, rapidly cited material. It is a measure of citation speed rather than of total impact.