Few can now doubt that open access (OA) to scholarly research is set to become an important feature of the scholarly communication landscape. What is less certain is how much of the world’s research literature is currently available on an OA basis, how fast OA is growing, and what percentage of the world’s academic and scientific literature will be OA in the long-term.
Trying to crunch the numbers is complicated by the fact that research papers can be made OA in two ways: Researchers can continue to publish in subscription journals and then make them freely available by self-archiving them in an institutional repository (Green OA), or they can pay to publish their work in an OA journal (either a pure Gold journal or a Hybrid OA journal) so that the publisher will make it freely available for them.
OA enthusiasts like librarian Heather Morrison — who publishes a series called “Dramatic Growth of Open Access” — tend to estimate OA occurrence and growth primarily by the simple counting of things.
In March, for instance, Morrison reported that there are now over 6,000 OA journals listed in the directory of open access journals (DOAJ), and implied that the number of OA articles is now growing more quickly than the number of papers being published in subscription journals. As she put it: “Data is presented that strongly suggests that the success rate for open access journals is already higher than that of subscription journals.”
In the same post, Morrison argued that by counting the number of papers flagged as OA on the Mendeley research sharing service we could conclude that self-archiving had grown by 171% in the first quarter of 2011.
Counting in this way presents an upbeat picture, suggests that the world is in the process of being flooded with OA, and that universal OA is just around the corner.
Refining the counts
Critics, however, point out that simple counting is too crude when trying to measure OA. Counting Gold OA journals, for instance, is not helpful since many of them publish just a handful of papers a year, if that.
Likewise, counting items that have been self-archived can be deceptive: Many records in institutional repositories will consist of metadata alone, or non-target items like presentations and other non-reviewed material.
Certainly publishers describe the incidence and growth of OA in a less upbeat manner. When I spoke to Springer’s Derk Haank at the end of last year, for instance, he estimated that only around 2% to 2.5% of the world’s papers are being published in Gold or Hybrid journals today.
And since the total number of research papers is growing at around 6% to 7% a year, he said, OA remains “just a drop in the ocean”.
In fact, predicted Haank, OA publishing will never be more than a niche activity. “I expect it to remain between 5% and 10% at a maximum,” he said.
Haank did not provide an estimate of Green OA, but implied that it was relatively low. Pointing out that he would be anxious if it did become commonplace he added, “But we are such a long way from that situation today that we are very easy going about author archiving.”
A few researchers, meanwhile, have been busy trying to arrive at more precise figures. When I last wrote on this topic in 2010 I spoke to a number of researchers, including Bo-Christer Björk.
Based at the Hanken School of Economics in Helsinki, Björk has undertaken several studies aimed at sizing the growth of OA, primarily Gold OA.
For a variety of reasons, Björk explained, this is not an easy thing to do. Nevertheless, when I spoke to him in January 2010 Björk estimated that Gold OA was probably increasing its share of the market by 0.5% per annum.
He added, however: “I have no evidence to show any acceleration in growth. On the contrary it seems that growth has been relatively stable, after a short expansive period when BioMed Central and PLoS were founded”.
“Tremendous growth of Gold OA”
Since then, Björk has taken a closer look at the many new OA journals that have been launched from 1993 - 2009, as well as the many subscription journals that have been converted into Gold journals.
There has also been the rise of “mega journals” like PLoS ONE, now the largest peer-reviewed journal in the world, and which expects to publish 12,000 papers in 2011 alone. In the wake of PLoS ONE’s success a number of PLoS ONE clones have recently been launched.
On June 13th 2011 Björk and colleagues published a new paper reporting an average annual growth rate since 2000 of 18% for the number of OA journals and 30% for the number of articles.
This, the paper suggests, “can be contrasted to the reported 3.5% yearly volume increase in journal publishing in general. In 2009 the share of articles in OA journals, of all peer reviewed journal articles, reached 7.7%. Overall, the results document a rapid growth in OA journal publishing over the last fifteen years.”
And in a note he posted on the American Scientist Open Access Forum (AmSci) Björk said that the results, “show the tremendous growth of gold OA over the past decade”.
As we said, Björk’s primary focus is on Gold OA. What about Green OA?
This is an area that Yassine Gargouri, a postdoctoral researcher who works with OA advocate Stevan Harnad at the Université du Québec à Montréal (UQAM), has been working on for the past four years.
Gargouri’s numbers suggest that between 2005 and 2010 the percentage of Green OA rose from about 15% per year to about 21%, which amounts to an increase of about 1% per year.
His numbers also suggest that introducing a Green mandate (requiring all an institution’s researchers to self-archive their papers) triples the yearly percentage of OA papers from the mandating institution.
Taken together with Björk’s work, this would seem to suggest that around 30% of the academic and scientific literature published in 2011 worldwide may now be freely available on the Web, two thirds of it as Green OA and one third of it as Gold OA.
Can Gold alone buy OA?
Nevertheless, it remains difficult to be precise about OA numbers, and especially difficult to make accurate predictions about future growth.
Like all attempts to understand and predict the world by means of numbers and statistics, much depends on how one derives them in the first place, how one crunches them, and how one subsequently interprets the results. In the case of OA, a key question that emerges is whether Gold OA is able on its own to accelerate the growth of OA to the degree that the OA movement would wish.
Why is it necessary to fret over such things? It is necessary for a number of reasons, but above all because if OA advocates knew exactly what was happening, and why, they would be able to put their main effort into those activities most likely to achieve their goal.
Vitally, they would be better able to answer a question that has plagued the movement for many years: Should the priority be given to Green or to Gold OA?
In the PDF file attached below I am publishing a Q&A interview with Gargouri. With a PhD in cognitive informatics, Gargouri has also participated in projects dealing with knowledge management, semantic web applications and ontologies. He has also taught in the computer science department at UQAM.
The interview includes contributions from Harnad — a leading OA advocate and self-styled archivangelist.
If you wish to read the interview please click on the link below.
I am publishing it under a Creative Commons licence, so you are free to copy and distribute it as you wish, so long as you credit me as the author, do not alter or transform the text, and do not use it for any commercial purpose.
To read the interview (as a PDF file) click here.
See also: John Whitfield Open access comes of age Nature, 21st June 2011