Align$^3$GR: Unified Multi-Level Alignment for LLM-based Generative Recommendation
Wencai Ye, Mingjie Sun, Shuhang Chen, Wenjin Wu, Peng Jiang
TL;DR
Problem: bridging semantic and behavioral gaps when applying LLMs to personalized recommendations. Approach: Align$^3$GR unifies token-level, behavior-level, and preference-level alignment via dual SCID tokenization, bidirectional SFT, and progressive DPO with SP-DPO and RF-DPO. Findings: achieves strong offline gains (e.g., +17.8% Recall@10 and +20.2% NDCG@10 on Instruments) and meaningful online revenue improvements in production deployments. Significance: provides a scalable, end-to-end blueprint for deploying LLM-based generative recommender systems in industry.
Abstract
Large Language Models (LLMs) demonstrate significant advantages in leveraging structured world knowledge and multi-step reasoning capabilities. However, fundamental challenges arise when transforming LLMs into real-world recommender systems due to semantic and behavioral misalignment. To bridge this gap, we propose Align$^3$GR, a novel framework that unifies token-level, behavior modeling-level, and preference-level alignment. Our approach introduces: Dual tokenization fusing user-item semantic and collaborative signals. Enhanced behavior modeling with bidirectional semantic alignment. Progressive DPO strategy combining self-play (SP-DPO) and real-world feedback (RF-DPO) for dynamic preference adaptation. Experiments show Align$^3$GR outperforms the SOTA baseline by +17.8% in Recall@10 and +20.2% in NDCG@10 on the public dataset, with significant gains in online A/B tests and full-scale deployment on an industrial large-scale recommendation platform.
