Hierarchical deep bidirectional self-attention model for recommendation

Abstract

This study proposes a bidirectional recommendation model to tackle the user cold start problem. We can predict the middle item when a user has only a few user-item interactions and enrich their interaction set accordingly. By recursively repeating this process, we can obtain enough interactions to make accurate item recommendations to the user. For instance, a user may buy a few items from an e-commerce site but also purchase other items from elsewhere, leading to incomplete information about their preferences. The proposed bidirectional recommendation model can fill the user's interaction history gaps, enabling accurate item recommendations even with limited data. In this thesis, we aimed to develop a recommendation system that imitates the behavior of today's e-commerce users' online purchasing experience. Our approach emphasized practicality, as we aimed to create a system that could be implemented easily in real-world e-commerce platforms. In doing so, we focused on developing an approach that could handle a large number of users and items found on such platforms while still maintaining high performance. By prioritizing these factors, we aimed to create a recommendation system that could be effectively applied in real-world scenarios. For future work, exploring combinations of the suggested algorithms for both layers would be worthwhile. Furthermore, examining the impact of algorithms proposed for the first layer or the user's shopping history enrichment algorithm on different recommendation systems would be beneficial. Ultimately, the most significant improvement is the application of proposed hierarchical recommendation network to cross-domain recommendation problems.