手法を比較

	Crown Indicator (CPP/FCSm)	g-Index (Egghe)
分野	計量書誌学	計量書誌学
系統	Process / pipeline	Process / pipeline
提唱年	1995	2006
提唱者	Henk F. Moed, R. E. De Bruin & Th. N. Van Leeuwen (CWTS Leiden)	Leo Egghe
種類	Field-normalized citation impact indicator (ratio of averages)	Author-level cumulative-citation impact index
原典	Moed, H. F., De Bruin, R. E., & Van Leeuwen, T. N. (1995). New bibliometric tools for the assessment of national research performance: Database description, overview of indicators and first applications. Scientometrics, 33(3), 381-422.	Egghe, L. (2006). Theory and practise of the g-index. Scientometrics, 69(1), 131-152.
別名	CPP/FCSm, old crown indicator, Leiden crown indicator, CWTS crown indicator	Egghe g-index, Egghe index, g index
関連	3	3
概要	The crown indicator, written CPP/FCSm, was the field-normalized citation impact measure developed at the Centre for Science and Technology Studies (CWTS) in Leiden and described by Moed, De Bruin, and Van Leeuwen in 1995. It compares a unit's observed citation rate with what would be expected given the fields, document types, and years in which it published. Specifically, it divides the citations per publication (CPP) by the mean field citation score (FCSm), forming a ratio in which a value of 1 marks performance exactly at the field average. For more than a decade it was CWTS's flagship indicator, until Waltman and colleagues showed in 2011 that its ratio-of-averages construction had statistical drawbacks and proposed the MNCS as a successor.	The g-index, introduced by Leo Egghe in 2006, is an author-level bibliometric indicator designed to repair a structural weakness of Hirsch's h-index: its insensitivity to the size of the most-cited papers. Where the h-index caps the credit any single paper can earn at h, the g-index lets exceptionally cited articles raise an author's score. It is defined as the largest number g such that the g most-cited papers together accumulate at least g-squared citations. Because it rests on cumulative rather than per-paper citation counts, the g-index always equals or exceeds the h-index and rewards researchers whose impact is concentrated in a few landmark works as well as those with broad, steady output.