Peterson, GJ; Presse, S; Dill, KA. 2010. Nonuniversal power law scaling in the probability distribution of scientific citations. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 107 (37): 16023-16027

[Eugene Garfield]

Peterson, GJ; Presse, S; Dill, KA. 2010. Nonuniversal power law scaling in the 
probability distribution of scientific citations. PROCEEDINGS OF THE NATIONAL 
ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 107 (37): 16023-
16027..

Author Full Name(s): Peterson, George J.; Presse, Steve; Dill, Ken A.
Language: English
Document Type: Article

Author Keywords: graph theory; master equation; h-index; preferential 
attachment; cumulative advantage
KeyWords Plus: ZIPFS LAW; NETWORKS; FLUCTUATIONS; COMPANIES; 
EVOLUTION

Abstract: We develop a model for the distribution of scientific citations. The 
model involves a dual mechanism: in the direct mechanism, the author of a new 
paper finds an old paper A and cites it. In the indirect mechanism, the author 
of a new paper finds an old paper A only via the reference list of a newer 
intermediary paper B, which has previously cited A. By comparison to citation 
databases, we find that papers having few citations are cited mainly by the 
direct mechanism. Papers already having many citations ("classics") are cited 
mainly by the indirect mechanism. The indirect mechanism gives a power-law 
tail. The "tipping point" at which a paper becomes a classic is about 25 
citations for papers published in the Institute for Scientific Information (ISI) 
Web of Science database in 1981, 31 for Physical Review D papers published 
from 1975-1994, and 37 for all publications from a list of high h-index chemists 
assembled in 2007. The power-law exponent is not universal. Individuals who 
are highly cited have a systematically smaller exponent than individuals who are 
less cited.

Addresses: [Presse, Steve; Dill, Ken A.] Univ Calif San Francisco, Dept 
Pharmaceut Chem, San Francisco, CA 94158 USA; [Peterson, George J.] Univ 
Calif San Francisco, Biophys Grad Grp, San Francisco, CA 94158 USA

Reprint Address: Dill, KA, Univ Calif San Francisco, Dept Pharmaceut Chem, San 
Francisco, CA 94158 USA.

E-mail Address: dill at maxwell.ucsf.edu
ISSN: 0027-8424
DOI: 10.1073/pnas.1010757107
Fulltext: http://www.pnas.org/content/107/37/16023.abstract