Thanks Stevan. Unfortunately that does not answer the question I posed, but a different question which is not relevant in the research being undertaken to see the adoption of OA practices amongst researchers, as opposed to the application of OA to articles which you have ably handled.
 As you have recognized, it only needs one author of a multi-author article to make the whole paper OA; however as we approach 100%, single-author articles will require that sole author to make his or her paper OA. (The question is irrelevant to Gold OA because all authors jointly agree to make the article OA, once.) It would be an interesting study to see amongst Green OA, whether the rate of making articles OA improves as the number of authors does. Hypothesis A: it will, but not linearly. Secondly one could look at the number of times an article is OA (ie the number of OA copies there are on the Internet). Hypothesis B: this measure should increase with the number of authors, though probably not linearly. Zipfâs law is more likely in these cases as earlier-listed authors are probably the more likely to take OA action. Is your crawled data capable of being re-interpreted this way?  I propose to do the following:  (1)  Estimate the total number of papers P published per year y, Py (2)  Estimate the average number of authors per paper for this corpus, m. (3)  Compute m x Py = N, an estimate of the number of active researchers.  The expected errors in N are: ·      The value of Py is not certain â neither ISI nor Scopus are complete. This leads to an under-estimate. ·      Not all researchers publish every year. This means that the number of researchers is again under-estimated. ·      Some researchers publish more than once per year. This is double-counting and results in an over-estimate. ISI or Scopus may be able to provide disambiguated estimates from their databases. ·      Unfortunately aggregating the number of years causes both the above errors to change â the first reducing, the second increasing. I have seen statements to the effect that an active researcher publishes at least once every three years, so the effective limit is 3 successive years.  Still, the information will be interesting and perhaps useful. It may be useful to do a pilot study in a single institution. Australian universities have complete citation databases of their publications, so it may be possible to check this type of data for a single institution. If it is a big one, the data may extrapolate.  Best wishes  Arthur  From: goal-boun...@eprints.org [mailto:goal-boun...@eprints.org] On Behalf Of Stevan Harnad Sent: Sunday, 1 January 2012 8:52 PM To: Global Open Access List (Successor of AmSci) Subject: [GOAL] Re: How many researchers are there?  Some suggestions:  (1) Estimate the total number of papers P published per year y, Py, rather than the number of researchers.  (2) Start with the Thompson-Reuters-ISI-indexed (or SCOPUS-indexed) subset.  (3) For Py, sample the web (Google Scholar) to see what percentage of it is freely available (OA).  Our latest rough estimate with this method, using a robot, is about 20%.  (Using estimates of the number of researchers, if the margin of error for the total is 1M - 10M then the margin of error for the percentage OA would be 10% - 100%, which is too big. Using known, published papers as the estimator also eliminates the multi-author problem.)  Cheers, Stevan  On 2011-12-31, at 6:25 PM, Arthur Sale wrote: I am trying to get a rough estimate of the number of active researchers in the world. Unfortunately all the estimates seem to be as rough as the famous Drake equation for calculating the number of technological civilizations in the universe: in other words all the factors are extremely fuzzy. I seek your help. My interest is that this is the number of people who need to adopt OA for us to have 100% OA. (Actually, we will approach that sooner, as the average publication has more than one author and we need only one to make it OA.  To share some thinking, let me take Australia. In 2011 it had 35 universities and 29,226 academic staff with a PhD. Let me assume that this is the number of research active staff. The average per institution is 835, and this spans big universities down to small ones. Australia produces according to the OECD 2.5% of the worldâs research, so letâs estimate the number of active researchers in the world (taking Australia as âtypicalâ of researchers) as 29226 / 0.025 = 1,169,040 researchers in universities. Note that I have not counted non-university research organizations (theyâll make a small difference) nor PhD students (there is usually a supervisor listed in the author list of any publication they produce).  Letâs take another tack. I have read the number of 10,000 research universities in the world bandied about. Letâs regard âresearch universityâ as equal to âPhD-granting universityâ. If each of them have 1,000 research active staff on average, then that implies 10000 x 1000 = 10,000,000 researchers.  That narrows the estimate, rough as it is, to         1.1M < no of researchers < 10M I can live with this, as it is only one power of ten (order of magnitude) between the two bounds. The upper limit is around 0.2% of the worldâs population.  Another tactic is to try to estimate the number of people whose name appeared in an author list in the last decade. Disambiguation of names rears its ugly head. This will also include many non-researchers in big labs, some of them will be dead, and there will be new researchers who have just not yet published, but I am looking for ball-park figures, not pinpoint accuracy. I havenât done this work yet.  Can we do better than these estimates, in the face of different national styles? It is even difficult to get one number for PhD granting universities in the US, and as for India and China @$#!  Arthur Sale University of Tasmania, Australia   _______________________________________________ GOAL mailing list GOAL@eprints.org http://mailman.ecs.soton.ac.uk/mailman/listinfo/goal  [ Part 2: "Attached Text" ] _______________________________________________ GOAL mailing list GOAL@eprints.org http://mailman.ecs.soton.ac.uk/mailman/listinfo/goal
