A Model for Readership of Astronomical Journals, From an Analysis of ADS Readership
Abstract
Astronomy is perhaps unique, in that it already has an integrated electronic information resource (ADS/Urania) which includes electronic access to nearly all the modern journal literature, and which is used by a large fraction of practitioners in the field, worldwide. The combined Urania logs, including the electronic journals and ADS, probably represent a fair sample, if not the majority, of the total readership in the field. Using the ADS logs we develop a four component model for how the astronomical literature is read, as a function of the age of an article, R = N + C + IM + H, where the first three terms are exponentials with very different time constants, and the fourth is a low level constant. R is the total readership; N is the readership of the latest issue of a journal; C is the readership of the current literature; I is the fraction of articles which are intermediate term interesting; M is the frequency of readership for interesting articles; so IM is the readership of intermediate term interesting articles; H is the readership of historical articles. The overwhelming majority of ADS use can be described accurately by R = C + IM; where I = I_0e(0.075T) , T is the age of the article in years, and I_0 is about 0.7, M = M_0e(.015T) , with M_0 equal to 2.5 reads per month, and C = C_0e(0.85T) , where C_0 is equal to 5 reads per month. Note that after about 4 years, when the C term has become small, the main factor is I, whether an article is read at all, not M, how many times an article is read.
 Publication:

American Astronomical Society Meeting Abstracts #194
 Pub Date:
 May 1999
 Bibcode:
 1999AAS...194.4407K