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. 2005 Nov 15;102(46):16569-72.
doi: 10.1073/pnas.0507655102. Epub 2005 Nov 7.

An index to quantify an individual's scientific research output

J E Hirsch  1
Affiliations

An index to quantify an individual's scientific research output

J E Hirsch. Proc Natl Acad Sci U S A. .

Abstract

I propose the index h, defined as the number of papers with citation number > or =h, as a useful index to characterize the scientific output of a researcher.

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Figures

Fig. 1.
Fig. 1.
Schematic curve of number of citations versus paper number, with papers numbered in order of decreasing citations. The intersection of the 45° line with the curve gives h. The total number of citations is the area under the curve. Assuming the second derivative is nonnegative everywhere, the minimum area is given by the distribution indicated by the dotted line, yielding a = 2 in Eq. 1.
Fig. 2.
Fig. 2.
Histogram giving the number of Nobel prize recipients in physics in the last 20 years versus their h index. The peak is at the h index between 35 and 39.
See this image and copyright information in PMC

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