PersonaDual: Balancing Personalization and Objectivity via Adaptive Reasoning
Xiaoyou Liu, Xinyi Mou, Shengbin Yue, Liang Wang, Yuqing Wang, Qiexiang Wang, Tianrui Qin, Wangchunshu Zhou, Zhongyu Wei
TL;DR
PersonaDual tackles the challenge of balancing personalization with objectivity in LLMs by enabling adaptive switching between two reasoning modes: general objective reasoning and personalized reasoning. It introduces a two-stage training framework: supervised fine-tuning to instill both modes, followed by DualGRPO, a prefix-aware reinforcement learning algorithm that optimizes context-sensitive mode selection. Empirical results show PersonaDual nearly neutralizes the negative impact of unaligned personalization on objective QA and even yields gains when personas are aligned, while preserving personalized benefits on subjective tasks. This approach advances reliable, user-adaptive AI by reducing personalization-induced errors and enabling beneficial personalization in a principled, controllable way.
Abstract
As users increasingly expect LLMs to align with their preferences, personalized information becomes valuable. However, personalized information can be a double-edged sword: it can improve interaction but may compromise objectivity and factual correctness, especially when it is misaligned with the question. To alleviate this problem, we propose PersonaDual, a framework that supports both general-purpose objective reasoning and personalized reasoning in a single model, and adaptively switches modes based on context. PersonaDual is first trained with SFT to learn two reasoning patterns, and then further optimized via reinforcement learning with our proposed DualGRPO to improve mode selection. Experiments on objective and personalized benchmarks show that PersonaDual preserves the benefits of personalization while reducing interference, achieving near interference-free performance and better leveraging helpful personalized signals to improve objective problem-solving.
