Date: Sat, 15 Nov 2003 15:08:36 +0530 From: Subbiah Arunachalam <arun@mssrf.res.in> Friends: Here is some evidence to show that open access papers are cited far more often than papers which are not in the open access domain. Based on some well-planned research! Here is an excerpt from a posting by Stevan Harnad to another list.. Arun ------- You may be interested in: <http://listserv.nd.edu/cgi-bin/wa?A2=ind0311&L=pamnet&D=1&O=D&P=1632> which is a report by the librarian liason of the AAS Pub board meeting. The relevant paragraph (at the end) is: "Finally, there was a very interesting brief report from Greg Schwarz (from the ApJ editorial office) on some work he's doing tracking citation rates of papers published in the ApJ based on whether they were posted on astro-ph or not. He studied samples from July-Dec. 1999 and July-Dec. 2002. The first interesting point is that 72% of the papers published in the latter period had appeared on astro-ph, although the submission rate to the server seems to be leveling off. He also noted that the number of authors per paper has been increasing along with the total length and that most astro-ph submissions are after acceptance by the journal. The really fascinating conclusion he's drawn, at least from my perspective, is that ApJ papers that were also on astro-ph have a citation rate that is _twice_ that of papers not on the preprint server. Moreover, this higher citation rate appears to continue once the time gap disappears (that is, papers on astro-ph are viewed about nine months ahead of the journal paper, but after several years of availability, the astro-ph papers are still being cited at a significantly higher rate)." You [Michael Kurtz, Astrophysics, Harvard] have shown some similar work already, but this seems nicely done. With the majority of ApJ papers going to astro-ph those which are not preprinted (and which are less referenced) seem the oddballs. I have been assuming that the higher citation rates for papers which are preprinted was due to the preprinting; perhaps the effect is that lower quality/interest papers are not preprinted. Can I ask for a clarification (because the word "preprinted," unlike "self-archived," is somewhat ambiguous): Are you specifically referring here to the prepublication part of an article's timeline, your point being that in astrophysics, where the publishers' versions are all effectively "open access" by the time they appear (in that they are all available to the entire worldwide astrophysical research community via site-licenses to the relatively small and closed group of journals involved), there are *still* twice as many citations of those papers that were self-archived before publication (as either pre-refereeing preprints or post-refereeing postprints or both) than to those that only became openly accessible when they became available as from the publisher? That would be very useful news both for the value of open access to eprints (preprints and postprints) in general and the value of prepublication self-archiving in particular, suggesting that (if we take Steve Lawrence's figures for the overall citation advantage of free online access to eprints over the its alternatives -- online or on-paper -- which is a citation advantage of 4.5) we see that a two-fold advantage already comes from free access to the prepublication phase alone. The causality, of course, is uncertain here, as you note: Is it that earlier open-access enhances the citation counts, or that the better articles are the ones that are being self-archived earlier? In any case, it is certainly a vote both for open access and for early self-archiving! Cheers, Stevan