Participatory Elicitation of User Model Dimensions for Active Ageing: The EMERGE Methodology - Barbarelli,A.; Santos,O.C.; Manjarrés,A.; Portaz,M.; Cabestrero,R.; Quirós,P.; Hermosilla,M.; Abril,M.; Pickin,S. (UMAP 2026 - Proceedings of the 34th ACM International Conference on User Modeling, Adaptation and Personalization, 2026)