Aiming to investigate the citation advantage of author-pays model, the present communication compares open access (OA) and Toll Access (TA) papers recognition in author-pays OA journals in 2007-2011. This is the first large scale study concentrating on all APC-funded OA journals published by Springer and Elsevier as the two greatest publishers authorizing and embracing the model. According to the research findings, the OA papers have been exponentially increased in recent years. They are, also, found to outperform the TA ones in their impacts whether in the annual comparisons or across disciplines. The annual OA citation advantages range from 21.36 % for 2009 to 49.71 % for 2008. Social Sciences and Humanities (with 3.14 %) and Natural Sciences (with 35.95 %) gain the lowest and the highest advantages, respectively. The citation advantage can be attributed to the higher visibility of the OA articles, implying the popularity and usefulness of the OA author-pays model to their readership. It may, also, have roots in the selectivity of the authors in choosing the author-pays outlet to publish their high-quality papers, signifying the overall prestige of the OA papers published in the model. Whatever may be the ultimate interpretation, i.e. correlation or causation, the OA citation advantage may encourage the authors who are willing to support OA movement, while seeking to get published in the well-established traditional journals. This may help approach the not-yetachieved critical mass necessary to evaluate the success of the model.

No abstract

This article examines the evolution of a collection of open access journals (OAJs,) indexed by the Science Citation Index (SCI; Thomson Scientific Philadelphia, PA) against four validity criteria including a free, immediate, full and constant access policy for at least 5 years. Few journals are found to be wrongly identified as OAJ or to have a dubious access policy. Some delayed journals evolved into gold OA; however, these are scarce compared to the number of journals that withdrew from gold OA to be an embargoed or a partially OAJ. A majority of the journals meet three of the criteria as they provide free and immediate access to their entire contents. Although a lot are found to follow a constant policy, a large number has an OA lifetime shorter than 5 years, due to the high frequency of newly launched or newly converted journals. That is the major factor affecting the validity of the collection. Only half of the collection meets all the requirements.

No abstract