The APC-Effect: Stratification in Open Access Publishing

Current implementations of Open Access (OA) publishing frequently involve Article Publishing Charges (APCs). Increasing evidence emerges that APCs impede researchers with fewer resources in publishing their research OA. We analysed 1.5 million scientific articles from journals listed in the Directory of Open Access Journals to assess average APCs and their determinants for a comprehensive set of journal publications, across scientific disciplines, world regions and through time. Levels of APCs were strongly stratified by scientific fields and the institutions’ countries, corroborating previous findings on publishing cultures and the impact of mandates of research funders. After controlling for country and scientific field with a multilevel mixture model, however, we found small to moderate effects of levels of institutional resourcing on the level of APCs. This is what we call the APC-Effect. Effects were largest in countries with low GDP, suggesting decreasing marginal effects of institutional resources when general levels of funding are high. Our findings provide further evidence on how APCs stratify OA publishing and highlight the need for alternative publishing models.