Styles + Persona-plug = Customized LLMs
Yutong Song, Jiang Wu, Shaofan Yuan, Chengze Shen, Jian Wang, Amir Rahmani, Nikil Dutt, Yu Wang
TL;DR
The paper reframes user personalization in LLM generation as a residual between a user’s true linguistic behavior and a neutral base model, enabling style-aware control without per-user fine-tuning. It introduces PsPLUG, a lightweight soft-prompt plug-in that injects a trainable prefix into a frozen backbone, learned via style-conditioned preference contrasts to separate persona from style. A unified style-persona balancing mechanism with an inference-time alpha control allows continuous trade-offs between personalization strength and adherence to explicit style instructions. Experiments on LaMP demonstrate improved persona alignment and robust style fidelity with minimal computational overhead, supporting scalable, style-aware personalization for LLMs.
Abstract
We discover a previously overlooked challenge in personalized text generation: personalization methods are increasingly applied under explicit style instructions, yet their behavior under such constraints remains poorly understood. To balance implicit personalization and explicit style, we formulate personalization as a distributional residual and propose PsPLUG, a lightweight soft-prompt plug-in trained with style-conditioned preference contrasts. Across LaMP benchmark, our framework improves persona alignment, maintains stylistic fidelity, and outperforms retrieval-based and soft-prompt baselines with minimal computation. These results show that residual modeling provides a simple and principled foundation for controllable, style-aware LLM personalization.
