The h-index is an index for quantifying the scientific productivity of physicists and other scientists based on their publication record. It was suggested in 2005 by Jorge E. Hirsch of the University of California, San Diego.
"The index is calculated based on the distribution of citations received by a given researcher's publications." Hirsch writes:
A scientist has index h if h of his N papers have at least h citations each, and the other (N - h) papers have at most h citations each. In other words, a scholar with an index of h has published h papers with at least h citations each. Thus, the h-index is the result of the balance between the number of publications and the number of citations per publication. The index is designed to improve upon simpler measures such as the total number of citations or publications, to distinguish truly influential scientists from those who simply publish many papers. The index is also not affected by single papers that have many citations. The index works properly only for comparing scientists working in the same field; citation conventions differ widely among different fields.
Some great economists' h-indices using SSCI database: