  The SOAP (Study of Open Access Publishing) project has compiled data on the
present offer for open access publishing in online peer-reviewed journals.
Starting from the Directory of Open Access Journals, several sources of data
are considered, including inspection of journal web site and direct inquiries
within the publishing industry. Several results are derived and discussed,
together with their correlations: the number of open access journals and
articles; their subject area; the starting date of open access journals; the
size and business models of open access publishers; the licensing models; the
presence of an impact factor; the uptake of hybrid open access.
