Item Cluster-aware Prompt Learning for Session-based Recommendation
Wooseong Yang, Chen Wang, Zihe Song, Weizhi Zhang, Philip S. Yu
TL;DR
CLIP-SBR addresses the limitation of relying solely on intra-session item relations in session-based recommendation by introducing a two-module framework: a global item relationship graph with Leiden-based clustering to capture inter-session connections, and cluster-aware soft prompts that are integrated into SBR training. By unifying intra- and inter-session interactions and injecting cluster-specific cues, it provides a universal, efficient mechanism to enhance diverse SBR models. Empirical results across three real-world datasets and eight baselines show consistent performance gains and reduced training time, validating the approach's practicality. This work advances SBR by enabling scalable cross-session knowledge transfer through prompt learning on item communities.
Abstract
Session-based recommendation (SBR) aims to capture dynamic user preferences by analyzing item sequences within individual sessions. However, most existing approaches focus mainly on intra-session item relationships, neglecting the connections between items across different sessions (inter-session relationships), which limits their ability to fully capture complex item interactions. While some methods incorporate inter-session information, they often suffer from high computational costs, leading to longer training times and reduced efficiency. To address these challenges, we propose the CLIP-SBR (Cluster-aware Item Prompt learning for Session-Based Recommendation) framework. CLIP-SBR is composed of two modules: 1) an item relationship mining module that builds a global graph to effectively model both intra- and inter-session relationships, and 2) an item cluster-aware prompt learning module that uses soft prompts to integrate these relationships into SBR models efficiently. We evaluate CLIP-SBR across eight SBR models and three benchmark datasets, consistently demonstrating improved recommendation performance and establishing CLIP-SBR as a robust solution for session-based recommendation tasks.
