Définition et exploitation des méta-rôles des utilisateurs pour la recherche d'information collaborative

Collaborative information retrieval is a particular setting involving a set of users sharing the same information need. In this context, the application of the division of labor policy through collaborators’ roles is generally used in order to structure the search session and enhance its retrieval effectiveness. In this paper, we propose to analyse the search features of pairwise collaborators allowing to identify their implicit roles according to research hypothesis based on their complementarity. We define the notion of collaborators’ meta-role which is (a) identified in real time, and (b) reinjected within a collaborative document ranking model. The experimental evaluation performed on search logs of real collaborative search session involving pairs of users highlights the effectiveness of our model with respect to individual-based or fixed roles-based search sessions. MOTS-CLÉS : recherche d’information collaborative, rôles, modèle d’ordonnancement, complémentarité des comportements