Abstract
Web personalization systems that have emerged in recent years enhance the retrieval process based on each user's interests and preferences. A key feature in developing an effective web personalization system is to build and model user profiles accurately. In this paper, we propose an approach that implicitly tracks users' browsing behaviour in order to build an ontology-based user profile. The main goal of this paper is to investigate techniques to improve the accuracy of this user profile. We focus in particular on the mapping process which involves mapping the collected web pages the user has visited to concepts in a reference ontology. For this purpose, we introduce two techniques to enhance the mapping process: one that maintains the user's general and specific interests without the user's involvement, and one that exploits browsing and search contexts. We evaluate the factors that impact the overall performance of both techniques and show that our techniques improve the overall accuracy of the user profile.