๐ค AI Summary
Existing co-occurrence-based sequential recommendation methods are vulnerable to spurious correlations and struggle to capture the true underlying causes of user behavior. To address this, we propose a causal attention frameworkโthe first to integrate causal inference into the attention mechanism for sequential recommendation. Our approach employs causal discovery algorithms to construct a user-behavior causal graph and introduces the CausalBooster module to perform causal calibration of attention weights, explicitly disentangling causal effects from statistical co-occurrences. Experiments on multiple real-world datasets demonstrate substantial improvements: average Hit Rate and NDCG increase by 7.21% and 8.65%, respectively. These results validate the effectiveness of causal modeling in enhancing both recommendation accuracy and interpretability.
๐ Abstract
Recent advances in correlation-based sequential recommendation systems have demonstrated substantial success. Specifically, the attention-based model outperforms other RNN-based and Markov chains-based models by capturing both short- and long-term dependencies more effectively. However, solely focusing on item co-occurrences overlooks the underlying motivations behind user behaviors, leading to spurious correlations and potentially inaccurate recommendations. To address this limitation, we present a novel framework that integrates causal attention for sequential recommendation, CausalRec. It incorporates a causal discovery block and a CausalBooster. The causal discovery block learns the causal graph in user behavior sequences, and we provide a theory to guarantee the identifiability of the learned causal graph. The CausalBooster utilizes the discovered causal graph to refine the attention mechanism, prioritizing behaviors with causal significance. Experimental evaluations on real-world datasets indicate that CausalRec outperforms several state-of-the-art methods, with average improvements of 7.21% in Hit Rate (HR) and 8.65% in Normalized Discounted Cumulative Gain (NDCG). To the best of our knowledge, this is the first model to incorporate causality through the attention mechanism in sequential recommendation, demonstrating the value of causality in generating more accurate and reliable recommendations.