Distillation Matters: Empowering Sequential Recommenders to Match the Performance of Large Language Models

Abstract

Owing to their powerful semantic reasoning capabilities, Large Language Models (LLMs) have been effectively utilized as recommenders, achieving impressive performance. However, the high inference latency of LLMs significantly restricts their practical deployment. To address this issue, this work investigates knowledge distillation from cumbersome LLM-based recommendation models to lightweight conventional sequential models. It encounters three challenges: 1) the teacher’s knowledge may not always be reliable; 2) the capacity gap between the teacher and student makes it difficult for the student to assimilate the teacher’s knowledge; 3) divergence in semantic space poses a challenge to distill the knowledge from embeddings. To tackle these challenges, this work proposes a novel distillation strategy, DLLM2Rec, specifically tailored for knowledge distillation from LLM-based recommendation models to conventional sequential models. DLLM2Rec comprises: 1) Importance-aware ranking distillation, which filters reliable and student-friendly knowledge by weighting instances according to teacher confidence and student-teacher consistency; 2) Collaborative embedding distillation integrates knowledge from teacher embeddings with collaborative signals mined from the data. Extensive experiments demonstrate the effectiveness of the proposed DLLM2Rec, boosting three typical sequential models with an average improvement of 47.97%, even enabling them to surpass LLM-based recommenders in some cases.

Publication
In Proceedings of the 18th ACM Conference on Recommender Systems 2024
Yu Cui
Yu Cui
Student

Yu Cui is currently a Eng.D student in ZLST, where he is supervised by Prof.Can Wang.

Bohao Wang
Bohao Wang
Student

I am a third-year Ph.D. student, and my supervisors are Prof. Chun Chen, Prof. Can Wang, and Prof. Jiawei Chen.

Heng Tang
Heng Tang
Student

Heng Tang is currently a Master student in ZLST, where he is supervised by Prof. Can Wang and Prof. Jiawei Chen.

Jiawei Chen
Jiawei Chen
陈佳伟 研究员