π€ AI Summary
Existing approaches to personalized text generation struggle to simultaneously maintain character consistency and style fidelity under explicit stylistic instructions. This work proposes a novel formulation that models personalization as a residual over the language modelβs output distribution. To this end, we introduce PsPLUG, a lightweight soft prompt plug-in that integrates style-conditioned preference-based contrastive learning. This approach enables efficient personalization without compromising the original style control mechanism. Requiring minimal computational overhead, PsPLUG significantly outperforms both retrieval-based and soft prompt baselines on the LaMP benchmark, while simultaneously improving character alignment and stylistic consistency.
π 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.