PersonaEdit: Representative Sample Selection for Personalized Model Editing

You-Mei Huang, Chung-Chi Chen, An-Zi Yen


Abstract
Personalization has attracted growing interest in LLM applications, yet existing retrieval-based approaches depend heavily on retrieval quality and degrade in long-term interactions. Model editing, which directly modifies internal model parameters to incorporate new knowledge, has demonstrated effective knowledge modification capabilities in factual knowledge editing tasks and may provide a potential solution for personalization. However, scaling model editing to personalization is non-trivial. Editing large amounts of user data increases computational cost and causes interference among edits, motivating the need for effective sample selection. To address this issue, we propose, PersonaEdit, a hidden representation clustering strategy that selects representative editing samples through proportional stratified sampling. Experiments show that model editing is effective for personalization, and that our selection strategy preserves most of the performance while substantially reducing the number of required editing samples. Beyond standalone editing, we find that combining model editing with retrieval-based prompt augmentation further improves personalization, as edited knowledge and retrieved context provide complementary information. These results demonstrate the potential of model editing as an efficient and scalable approach for LLM personalization.
Anthology ID:
2026.findings-emnlp.894
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
18945–18960
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.894/
DOI:
Bibkey:
Cite (ACL):
You-Mei Huang, Chung-Chi Chen, and An-Zi Yen. 2026. PersonaEdit: Representative Sample Selection for Personalized Model Editing. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 18945–18960, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
PersonaEdit: Representative Sample Selection for Personalized Model Editing (Huang et al., Findings 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.findings-emnlp.894.pdf