An Experiment to Evaluate how to Better Present User Models to the Users

The externalisation of user models may allow users to understand how a user-adapted Web application makes its adaptation decisions, enabling them to inspect and modify the values stored in their user model. When externalising a user model both the underlying representation of the user model and the visualization used to present it have to be taken into account. In this paper we present a study aimed at evaluating different ways to represent and visualize user models. We use a social recommender system in a cultural events domain (iCITY) as case study. To our purposes, we conducted two experiments: i) a large between-subjects on-line evaluation aimed at confronting different representation and visualization modalities; ii) a within-subjects experiment aimed at confronting the same experimental condition.