Phil Davis wrote:
> Based on our analysis, we found that a quality differential is
> a more plausible explanation -- the reason why arXiv-deposited
> articles receive more citations is simply because they are
> better articles, not because of some advantage conveyed through
> increased access. If Open Access can explain the citation
> advantage (and we did confirm one), it is only responsible for
> giving an advantage to already highly-cited articles.
Data I collected for philosophy, political science, engineering
and mathematics do not support this hypothesis that OA causes
more citations for better articles only (given that one uses
overall citations as a rough measure of quality).
These data were collected for my article, "Do Open Access
Articles Have a Greater Research Impact?" (C&RL Sept 2004,
http://eprints.rclis.org/archive/00002309/), but at that time I
had not looked at the distribution of OA and non-OA articles by
citations. Graphs of those results are posted at
http://www.lib.ncsu.edu/staff/kantelman/OA_by_citations.xls.
These data show OA citation advantage across all articles with
more than zero citations. It could be argued that OA helps to
get the first citation. It's also striking, I think, how similar
the graphs are even though the rates of OA vary greatly between
these disciplines (between 17% and 69%).
________________________________________
Kristin Antelman
Associate Director for the Digital Library
NCSU Libraries
Box 7111
Raleigh, NC 27696-7111
(919) 515-7188 Fax (919) 515-3628
Received on Tue Mar 21 2006 - 12:39:52 GMT