hIndex Hindex was born n We need an
h-Index
H-index was born ! n We need an Index both to include quantity & also quality of an authors' paper ü Productivity ü Impact ü Not affected by “big hits” ü Not affected by “noise”
Hirsch J E [b. 1953] Jorge Eduardo Hirsch Buenos Aires, Argentina h-Index: 41; 22 AUG 2014 Nationality Fields Argentine American Thesis Low-temperature thermodynamic properties of a random anisotropic antiferromagnetic chain (1980) Physicist
Hirsch J E - Original Paper An index to quantify an individual’s scientific research output J. E. Hirsch Department of Physics, University of California, San Diego, La Jolla, CA 92093 -0319 Abstract. I propose the index h, defined as the number of papers with citation number higher or equal to h, as a useful index to characterize the scientific output of a researcher. Proceedings of the National Academy of Sciences of the United States of America Volume 102, Issue 46, 15 November 2005, Pages 16569 -16572
Definition A scientist has index h if h of his/her Np papers have at least h citations each, and the other (Np − h) papers have no more than h citations each.
Definition n A scientist has h-index h if ¨h of his Np have received at least h citations each ¨ the rest Np-h articles have received no more than h citations each
Definition In other words, a scholar with an index of h has published h papers each of which has been cited in other papers at least h times.
H-index Concept through its Graph
The h-index A scientist has index h if h of his or her Np papers have at least h citations each and the other ( Np – h ) have at least ≤ h citations each Doc 1 2 3 4 5 6 7 8 9 10 11 49 23 15 14 6 3 1 1 0 0 0 Cit
H-index example Author A Doc 1 2 3 4 5 6 7 8 9 Cit 55 45 20 10 5 4 3 2 1 Author B Doc 1 2 3 4 Cit 25 20 9 6 10
H-Index - How to calculate by Author A Author B Author C hand? & G-index Article 1 2 3 4 5 6 7 8 h-index G-index Citations Article 10 1 6 2 6 6 3 0 6 6 3 4 5 6 7 8 h-index G-index Citations Article 30 1 27 2 26 16 6 3 2 1 5 10 3 4 5 6 7 8 h-index G-index Citations 230 190 90 34 30 2 0 1 5 24
Another example (Cites/Paper) Author 1 Author 2 Author 3 Paper 1 100 50 15 Paper 2 90 50 15 Paper 3 70 45 14 Paper 4 50 45 14 Paper 5 35 45 14 Paper 6 4 4 3 Paper 7 4 3 3 Paper 8 1 1 2 Paper 9 1 1 0 Paper 10 0 1 0 Total Cites 355 245 80 Avg. Cites/Paper 35. 5 24. 5 8. 0 h-Index
Characteristic § Thus, the h-index reflects both 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.
The h-index n Meaningful when compared to others within the same discipline area. Researchers in one field may have very different h-indices than researchers in another (e. g. Life Sciences vs. Physics).
H-Index Advantages n n The h-index was intended to address the main disadvantages of other bibliometric indicators, such as total number of papers or total number of citations. It simultaneously measure the quality and sustainability of scientific output, as well as, to some extent, the diversity of scientific research.
H-index drawbacks Like impact factors depends on subject area n It is a growing function over time n It does NOT show the current activity or inactivity of the author w Disadvantageous for younger researchers (without previous track record) n Scientists with short scientific life are out of competition n
My h-index is bigger than yours! Edward Witten Physicist h=132 But more people know who I am! Stephen Hawking Physicist h=62
HOW DO I CALCULATE THE h-index OF MY SEARCH RESULTS? Web of Science - Citation reports n Scopus - Citation Tracker n No database lists all articles. You must be aware of the difficulties of comprehensively searching for the publications of an author or group. n Help is available in both databases. n
h-Index at Career Level According to Hirsch: § § § For physicists, a value for h = 12 - Associate professor at major research universities A value of about 18 - Professorship, 15– 20 could mean a fellowship in the American Physical Society, and 45 or higher could mean membership in the United States National Academy of Sciences. About 100 in India – Bharat Ratna
Publications @ University of Delhi
University of Delhi: h-Index
Publications @ Physics and Astrophysics, DU
Physics and Astrophysics, DU : h-Index
Rao, CNR : Year wise citations
Rao, CNR : h-Index 105
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