手法を比較

	ジャーナルインパクトファクター	Ulrichsweb Global Serials Directory
分野	計量書誌学	計量書誌学
系統	Process / pipeline	Process / pipeline
提唱年	1955	1932
提唱者	Eugene Garfield, Institute for Scientific Information (ISI)	Bowker (originally R.R. Bowker), now ProQuest LLC
種類	Metric	Database
原典	Garfield, E. (1972). Citation analysis as a tool in journal evaluation. Science, 178(4060), 471-479.	ProQuest. (2024). Ulrichsweb: Global Serials Directory. Retrieved from https://ulrichsweb.serialssolutions.com/
別名	IF, JIF, Impact Factor, 2-year Impact Factor	Ulrichsweb, Ulrich's International Periodicals Directory, Ulrich's Directory
関連	5	4
概要	Journal Impact Factor (JIF) is a metric developed by Eugene Garfield in 1955 and published annually by Clarivate Analytics through Journal Citation Reports (JCR). It measures the average citation frequency of articles published in a journal over a two-year window, serving as a proxy for journal prestige and influence. A journal's Impact Factor equals the number of citations received in year Y to articles published in Y-1 and Y-2, divided by the number of citable items published in that same window. Despite widespread adoption in research evaluation, Impact Factor has significant limitations and critics argue it conflates journal prestige with article quality.	Ulrichsweb is a comprehensive, subscription-based global serials directory cataloging over 300,000 print and electronic journals, magazines, newspapers, and other periodical publications. Developed by ProQuest (originally R.R. Bowker), Ulrichsweb has served librarians and researchers for over 90 years as the authoritative source for journal metadata, publication information, and peer-review verification. A unique feature is Ulrichsweb's verification program: editorial staff contact journals directly to confirm peer-review claims, marking journals as 'refereed' only after validation. This verification process distinguishes legitimate peer-reviewed journals from predatory publishers falsely claiming peer review.