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

Purpose This article investigates challenges in reconciling heterogeneous records across cultural institutions, focusing on art historical photo archives within the PHAROS association. Design/methodology/approach Through case studies, the study analyses reconciliation workflows and cataloguing traditions, with attention to institutional contexts, data granularities and modelling strategies. Findings 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. Practical implications Insights from PHAROS provide guidance for designing more robust, interoperable and sustainable cultural heritage infrastructures. Originality/value The article highlights the need to model uncertainty explicitly, offering a framework that connects technical reconciliation methods with institutional practices.