Mendeley: Measuring OA rates

Having talked about Mendeley's OA deposit rates in my last blog post, I thought it worthwhile to check how representative my chosen discipline (Computer Science) was. Rather than download the entire community for each other discipline, I have performed a quick and dirty sample of some of the available literature in each discipline using the search function. Each Mendeley search result offers the option of saving the PDF (if available) to your library, so it is a simple matter to wget some search results and grep for PDFs.

The table below shows the results of this procedure for 11 disciplines (two illustrative keywords each). The "available PDFs" column records the number of PDFs offered on the first page of the search results (each page contains 200 results); the total number of results shows the relative coverage of the topic in Mendeley.

Computer Science appears to be in the 5-10% range of OA (18 or 11 PDFs out of a page of 200 results) which does seem to be just about average. Social Science, Medicine, Health Science, Economics and the Humanities appear to have fewer PDFs and Maths and Physics appear to have rather more.

Search term	Discipline	Available PDFs	Total Results
chromatography	Chem	10	14260
crystallography	Chem	27	4921
JAVA	CS	18	848
software	CS	11	15185
geology	Earth	36	4180
hydrodynamic	Earth	40	2853
econometrics	Economics	13	565
microeconomics	Economics	5	88
biodiversity	Env	14	4668
climate	Env	14	13003
nursing	Health	6	10723
palliative	Health	6	1978
archaeology	Hum	6	1730
Foucault	Hum	11	248
algebra	Math	101	4424
cohomology	Math	171	525
cancer	Med	11	52315
pharmacology	Med	4	62285
quasar	Phys	127	556
telescope	Phys	101	2347
cognition	Psy	11	18805
schizophrenia	Psy	17	4055
criminology	SocSci	2	154
sociology	SocSci	2	2005

Mendeley: Download vs Upload Growth

There was a lot of talk about Mendeley at OAI7 in Geneva, especially the news that in the first quarter of 2011 the number of articles downloaded for free jumped from 300,000 to 800,000. That's really good news, confirming Mendeley as a successful service in the Open Access domain. Having done an analysis of Mendeley's impact on Open Access (see Comparing Social Sharing of Bibliographic Information with Institutional Repositories) just under a year ago, I thought I'd repeat the analysis to see the extent of the impact of their growth on deposits as well as downloads.

Results: the number of members of the Computer Science discipline appears to be 2.2x larger than last August (increased to 74736 from 34230.) Of these, only 12102 appear in the Computer Science directory listing, whose contents are now filtered by Mendeley according to their "profile completion"; the gross number was kindly provided for me by Steve Dennis at Mendeley. This filtering takes care of the long tail of accounts that have never been used. Of the filtered users, 1676 are "OA active", having publicly shared at least one PDF document (up 21% on last August). The total number of PDFs shared by this group is 8014, up 16% on last August with 4.8 PDFs being shared per "active OA user" (down from 5.0 last August).

So a big increase in user numbers results in a small increase in publicly shared PDFs, confirming (I think) that Mendeley are not preaching to the choir, and are mainly attracting users who are not already "OA active". Users of Mendeley have clearly transitioned from "scholarly knowledge collectors" to "scholarly knowledge sharers". The challenge still remains how to change their behaviour from "scholarly asset maintainers" to "scholarly asset sharers".