User models have been defined since the 1980s, mainly for the purpose of building context-based, user-adaptive applications. However, the advent of social networked media, serious games, and crowdsourcing/human computation platforms calls for a more pervasive notion of user model, capable of representing the multiple facets of social users and performers, including their social ties, interests, capabilities, activity history, and topical affinities. In this paper, we define a comprehensive model able to cater for all the aspects relevant for applications involving social networks and human computation; we capitalize on existing social user models and content description models, enhancing them with novel models for human computation and gaming activities representation. Finally, we report on our experiences in adopting the proposed model in the design and implementation of three socially enabled human computation platforms.@en

User models have been defined since the '80s, mainly for the purpose of building context-based, user-adaptive applications. However, the advent of social networked media, serious games, and crowdsourcing platforms calls for a more pervasive notion of user model, capable of representing the multiple facets of a social user, including his social ties, capabilities, activity history, and topical affinities. In this paper, we overview several user models proposed recently to address the platform-independent representation of users embedded in a social context, and discuss the features of the CUbRIK user model, which is designed to support multi-platform human computation applications where users are called as collaborators in the resolution of complex tasks found in the multimedia information retrieval field.

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