Towards Conversational Recommender Systems
Konstantina Christakopoulou*, University of Minnesota; Katja Hofmann, Microsoft; Filip Radlinski, Microsoft
People often ask others for restaurant recommendations as a way to discover new dining experiences. This makes restaurant recommendation an exciting scenario for recommender systems and has led to substantial research in this area. However, most such systems behave very differently from a human when asked for a recommendation. The goal of this paper is to begin to reduce this gap.
In particular, humans can quickly establish preferences when asked to make a recommendation for someone they do not know. We address this cold-start recommendation problem in an online learning setting. We develop a preference elicitation framework to identify which questions to ask a new user to quickly learn their preferences. Taking advantage of latent structure in the recommendation space using a probabilistic latent factor model, our experiments with both synthetic and real world data compare different types of feedback and question selection strategies. We ﬁnd that our framework can make very effective use of online user feedback, improving personalized recommendations over a static model by 25% after asking only 2 questions. Our results demonstrate dramatic beneﬁts of starting from ofﬂine embeddings, and highlight the beneﬁt of bandit-based explore-exploit strategies in this setting.
Filed under: Recommender Systems