A Survey on Large Language Models for Personalized and Explainable Recommendations
Junyi Chen
TL;DR
This survey analyzes how Large Language Models can enhance personalization and explainability in Recommender Systems, with a focus on prompt-based and parameter-efficient strategies. It covers transformer-based NLG architectures, pre-training vs. prompting, and PEFT methods, as well as PEG-specific techniques like PEPLER and rationale/in-text learning, alongside evaluation metrics for quality and diversity. The paper also discusses PEG-related challenges such as cold-start and biases, highlighting approaches like PromptRec and bias-mitigating prompts to address them. Together, these insights offer a roadmap for building scalable, transparent, and fair LLM-enabled RS that can generate natural language explanations aligned with user needs.
Abstract
In recent years, Recommender Systems(RS) have witnessed a transformative shift with the advent of Large Language Models(LLMs) in the field of Natural Language Processing(NLP). These models such as OpenAI's GPT-3.5/4, Llama from Meta, have demonstrated unprecedented capabilities in understanding and generating human-like text. This has led to a paradigm shift in the realm of personalized and explainable recommendations, as LLMs offer a versatile toolset for processing vast amounts of textual data to enhance user experiences. To provide a comprehensive understanding of the existing LLM-based recommendation systems, this survey aims to analyze how RS can benefit from LLM-based methodologies. Furthermore, we describe major challenges in Personalized Explanation Generating(PEG) tasks, which are cold-start problems, unfairness and bias problems in RS.
