How long before open access in French social sciences and humanities journals?

The aim of this study is to evaluate the merits of the introduction of the principle of open access to research in the humanities and social sciences (HSS) in France, using a study of its effects on the consultation of articles. We want to know if a free access policy improves the visibility of research, and if so, to what extent. The study shines important light on decision making about the dissemination of research results and on the effect of restricted access (for both researchers and the broader public) to research results. At stake in this debate are the choice of duration of the open-access embargo period, that is, the delay between time of publication and when the journal makes it freely available (delayed access journals), and the length of the self-archiving embargo, that is, the minimum time before the journal allows authors to self-archive their articles on the web (open access mandate). This inquiry consists of quantifying the impact of the duration of the embargo on the journal's audience and on research. The findings of our investigation indicate that a barrier to dissemination results in a loss of audience for the journal, starting from the first year. Since the marginal costs of making articles available on-line are low to non-existent, this loss of readers represents what is called a "deadweight loss". Our results therefore favour the introduction of a relatively short embargo (less than one year) rather than the durations discussed in public debates about HSS research (two to three years).