When evaluating models for the financing of Diamond Open Access publications, the costs, their appropriateness and transparency are closely interdependent topics. More importantly, these are highly relevant criteria for institutions choosing to financially support Diamond Open Access publications. Consequently, the topic has its separate section in KOALA's Requirements that apply to publications benefitting from consortial funding via KOALA. For libraries, publications represent costs, and thus they need detailed information on the publications; that entails affiliations of authors and localized statistics, as well as costs (current and upcoming). To facilitate these analyses on the part of the institutions, TIB provides the Diamond Funding Navigator, a free website providing a comprehensive overview of consortial offers like KOALA - and currently more than a dozen other offers. General information about the offers is supplemented by data on the output of the publications supposed to be funded. This data is retrieved by OpenAlex and queries can be easily customized. At the same time, TIB encourages a holistic view on publications that doesn't rely solely on apparent (and pontentially only short-term) financial cost, but also opportunity costs and non-financial criteria. The transparency that the Diamond Funding Navigator provides in a variety of dimensions helps to appreciate these aspects as well. In our short talk and poster, we present findings and insights from the KOALA projects and the ongoing KOALA service at TIB with a focus on the topic of cost transparency. In addition, we show how the Diamond Funding Navigator can support libraries in their workflows for decision-making on Diamond OA financing and increase cost transparency.
Eppelin et al. (Fri,) studied this question.