AuthorMix: Modular Authorship Style Transfer via Layer-wise Adapter Mixing

Sarubi Thillainathan, Ji-Ung Lee, Michael Sullivan, Alexander Koller


Abstract
The task of authorship style transfer involves rewriting text in the style of a target author while preserving the meaning of the original text. Existing style transfer methods train a single model on large corpora to model all target styles at once: this high-cost approach offers limited flexibility for target-specific adaptation, and often sacrifices meaning preservation for style transfer. In this paper, we propose AuthorMix: a lightweight, modular, and interpretable style transfer framework. We first train individual, style-specific LoRA adapters on a small set of high-resource authors: this allows for the rapid training of specialized adaptation models for each new target using layer-wise adapter mixing via reinforcement learning, necessitating only a handful of target- style training examples. AuthorMix ranks first on the combined style–meaning score among all baselines, including GPT-5.1, and substantially improves meaning preservation over the trained baselines; under human evaluation it is the only method best-or-tied on every dimension.
Anthology ID:
2026.emnlp-main.2215
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
50382–50416
Language:
URL:
https://aclanthology.org/2026.emnlp-main.2215/
DOI:
Bibkey:
Cite (ACL):
Sarubi Thillainathan, Ji-Ung Lee, Michael Sullivan, and Alexander Koller. 2026. AuthorMix: Modular Authorship Style Transfer via Layer-wise Adapter Mixing. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 50382–50416, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
AuthorMix: Modular Authorship Style Transfer via Layer-wise Adapter Mixing (Thillainathan et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.2215.pdf