Re: OA advantage = EA + (AA) + (QB) + QA + (CA) + UA

From: Stevan Harnad <>
Date: Wed, 21 Jun 2006 20:44:40 +0100

    Pertinent Prior AmSci Topic Threads:

    "Early Download Impact Predicts Later Citation Impact" (Sep 2004)

    "OA advantage = EA + AA + QB + OA + UA" (Sep 2004)

On Wed, 21 Jun 2006, Ian Rowlands wrote:

> Several recent studies (e.g. Thomson Scientific, Eysenbach) have
> indicated that open access articles are more likely to be cited sooner
> than tolled access articles. This is an argument that, on the face
> of it, provides a powerful argument for open access: it speeds up
> scientific workflow. Can anyone supply a testable hypothesis for this?
> I can quite easily understand how open access leads to MORE use, thus
> higher citation. But speedier citation? What are the plausible cause
> and effect arguments here?

OA not only increases but accelerates citations for the following reasons:

    (1) OA can start before publication, at the preprint stage. Preprints
    can be self-archived, used, and cited even before they have reached
    the article (postprint) stage.

    (2) Both preprints and postprints can be cited by (subsequent)
    preprints, and preprints can be updated many times, unlike a
    published postprint, which is etched in stone (although the the
    practice of posting a postpublication revision -- a post-postprint --
    in increasing too).

   (3) Brody et al. (2005) showed that the interval between first
   posting of either preprints or postprints and the peak of curve for
   first citations of them has been getting earlier and earlier across the
   years as self-archiving has grown (in physics): papers are citing and
   getting cited earlier and earlier in the research/publication cycle.

   (4) This "Early Access" (EA) advantage is so great that some
   (e.g. Kurtz 2004) have concluded that it may be the biggest factor
   in the OA citation advantage (Harnad 2005).

   (5) Before there can be citation, there has to be access (at least
   in the case of serious scholarship). That means downloads precede
   citations: They also correlate with citations later on. Downloads
   can now happen earlier and earlier (Brody et al. 2005)

   (6) For most papers, even in disciplines that do not self-archive
   preprints, the self-archiving of a postprint means earlier and wider
   accessibility to potential users than publishing alone does.

Note, however, that there have been *many* more and earlier reports of
the OA impact advantage (both in terms of increased citations/downloads
and accelerated citations/downloads) than the two studies just mentioned
by Rowlands, and that most of them are based on OA self-archiving rather
than on OA publishing. See Steve Hitchcock's longstanding Bibliography
of Findings on the OA Advantage (and the sample studies below):

Brody, T. and Harnad, S. (2004) Comparing the Impact of Open Access (OA)
vs. Non-OA Articles in the Same Journals. D-Lib Magazine 10(6).

Brody, T., Harnad, S. and Carr, L. (2005) Earlier Web Usage Statistics
as Predictors of Later Citation Impact. Journal of the American
Association for Information Science and Technology (JASIST).

Hajjem, C., Harnad, S. and Gingras, Y. (2005) Ten-Year
Cross-Disciplinary Comparison of the Growth of Open Access and How it
Increases Research Citation Impact. IEEE Data Engineering Bulletin 28(4)

Harnad, S. (2005) OA Impact Advantage = EA + (AA) + (QB) + QA + (CA) + UA.

Kurtz, M. J., Eichhorn, G., Accomazzi, A., Grant, C. S., Demleitner,
M., Murray, S. S. (2004) The Effect of Use and Access on Citations.
Information Processing and Management, 41 (6): 1395-1402

Stevan Harnad
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Received on Wed Jun 21 2006 - 20:56:42 BST

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