Using Emotion Diversification Based on Movie Reviews to Improve the User Experience of Movie Recommender Systems
Lior Lansman, Osnat Mokryn, Lijie Guo, Mehtab Iqbal, Bart P. Knijnenburg · ACM Transactions on Interactive Intelligent Systems · 2025
Diversifying movie recommendations is an effective way to address choice overload, a phenomenon where recommenders generate lists with highly similar recommendations that are difficult to choose from. However, existing diversification algorithms often rely on latent features, which limits their interpretability and makes it less clear why a particular set of movies is recommended. Given that movies are designed to elicit emotional responses, researchers have suggested leveraging these responses to enhance recommender system performance. This study introduces a novel “emotion diversification” approach, which diversifies movie recommendations based on emotional signals extracted from audience reviews. We evaluate this method against latent and non-diversified baselines in a controlled user study (N = 115), finding that it significantly improves perceived taste coverage and system satisfaction without compromising recommendation quality. Going beyond the traditional rating- and/or interaction data used by traditional recommender systems, our work demonstrates the user experience benefits of extracting emotional data from rich, qualitative user feedback and using it to give users a more emotionally diverse set of recommendations.