Many-to-many. Usability challenges of entity reconciliation in art history and photographic studies

Abstract: This article investigates challenges in reconciling heterogeneous records across cultural institutions, focusing on art historical photo archives within the PHAROS consortium. Through case studies, the study analyses reconciliation workflows and cataloguing traditions, with attention to institutional contexts, data granularities, and modelling strategies. Reconciliation is seldom a one-to-one operation. Ambiguities, incomplete data, shifting attributions, and varying practices shape outcomes. Strategies observed include the creation of anonymous or collective entities, the use of umbrella terms, the addition of uncertainty qualifiers, and reticence when ambiguity cannot be resolved. The article highlights the need to model uncertainty explicitly, offering a framework that connects technical reconciliation methods with institutional practices. Insights from PHAROS provide guidance for designing more robust, interoperable, and sustainable cultural heritage infrastructures.