Representing context in Web search with ontological user profiles

Abstract

One of the key factors for effective personalization of information access is the user context. We propose a framework which integrates several critical elements that make up the user context, namely, the user's short-term behavior, semantic knowledge from ontologies that provide explicit representations of the domain of interest, and long-term user profiles revealing interests and trends. Our proposed approach involves implicitly building ontological user profiles by assigning interest scores to existing concepts in a domain ontology. These profiles are, therefore, maintained and updated as annotated instances of a reference domain ontology. We propose a spreading activation algorithm for maintaining the interest scores in the user profile based on the user's ongoing behavior. Our experimental results show that the user context can be effectively utilized for Web search personalization. Specifically, re-ranking the search results based on interest scores derived from the semantic evidence in an ontological user profile provides better search results by proficiently bringing results closer to the top when they are most relevant to the user. © Springer-Verlag Berlin Heidelberg 2007.