User modeling for adaptive news access

We present a framework for adaptive news access, based on machine learning techniques specifically designed for this task. First, we focus on the syst em's general functionality and system architecture. We then describe the in terface and design of two deployed news agents that are part of the describ ed architecture. While the first agent provides personalized news through a web-based interface, the second system is geared towards wireless informat ion devices such as PDAs (personal digital assistants) and cell phones. Bas ed on implicit and explicit user feedback, our agents use a machine learnin g algorithm to induce individual user models. Motivated by general shortcom ings of other user modeling systems for Information Retrieval applications, as well as the specific requirements of news classification, we propose th e induction of hybrid user models that consist of separate models for short -term and long-term interests. Furthermore, we illustrate how the described algorithm can be used to address an important issue that has thus far rece ived little attention in the Information Retrieval community: a user's info rmation need changes as a direct result of interaction with information. We empirically evaluate the system's performance based on data collected from regular system users. The goal of the evaluation is not only to understand the performance contributions of the algorithm's individual components, bu t also to assess the overall utility of the proposed user modeling techniqu es from a user perspective. Our results provide empirical evidence for the utility of the hybrid user model, and suggest that effective personalizatio n can be achieved without requiring any extra effort from the user.