Sequential Recommendation with Collaborative Explanation via Mutual Information Maximization

Current research on explaining sequential recommendations lacks reliable benchmarks and quantitative metrics, making it difficult to compare explanation performance between different models. In this work, we propose a new explanation type, namely, collaborative explanation, into sequential recommendation, allowing a unified approach for modeling user actions and assessing the performance of both recommendation and explanation. We accomplish this by framing the problem as a joint sequential prediction task, which takes a sequence of user's past item-explanation pairs and predicts the next item along with its associated explanation. We propose a pipeline that comprises data preparation and a model adaptation framework called Sequential recommendation with Collaborative Explanation (SCE). This framework can be flexibly applied to any sequential recommendation model for this problem. Furthermore, to address the issue of inconsistency between item and explanation representations when learning both sub-tasks, we propose Sequential recommendation with Collaborative Explanation via Mutual Information Maximization (SCEMIM). Our extensive experiments demonstrate that: (i) SCE framework is effective in enabling sequential models to make recommendations and provide accurate explanations. (ii) Importantly, SCEMIM enhances the consistency between recommendations and explanations, leading to further improvements in the performance of both sub-tasks.