Understanding differences of the OA uptake within the German University landscape (2010–2020): Part 2—repository-provided OA

This article is the second part of the investigation of the determinants for the uptake of Open Access (OA). While the first part focusses on journal-based OA (hybrid and full OA) (Taubert et al. in Scientometrics 128(6):3601–3625, 2023), the article at hand investigates the determinants for the uptake of institutional and subject repository OA in the university landscape of Germany. Both articles consider three types of factors: the disciplinary profile of universities, their OA infrastructures and services and large transformative agreements The article also apply a conjoint methodological design: the uptake of OA as well as the determinants are measured by combining several data sources (incl. Web of Science, Unpaywall, an authority file of standardised German affiliation information, the ISSN-Gold-OA 4.0 list, and lists of publications covered by transformative agreements). For universities’ OA infrastructures and services, a structured data collection was created by harvesting different sources of information and by manual online search. To determine the explanatory power of the different factors, a series of regression analyses was performed for different periods and for both institutional as well as subject repository OA. Given that both articles derive from the same project, there is a thematical overlap in the methods and data section. As a result of the regression analyses, the most determining factor for the explanation of differences in the uptake of both repository OA-types turned out to be the disciplinary profile, whereas all variables that capture local infrastructural support and services for OA turned out to be non-significant. The outcome of the regression analyses is contextualised by an interview study conducted with 20 OA officers of German universities. The contextualisation provides hints that the original function of institutional repositories, offering a channel for secondary publishing is vanishing, while a new function of aggregation of metadata and full texts is becoming of increasing importance.