LoRMA: Low-Rank Multiplicative Adaptation for LLMs

Harsh Bihany, Shubham Patel, Ashutosh Modi


Abstract
Large Language Models have shown remarkable capabilities in the NLP domain. Their effectiveness can mainly be attributed to their ability to adapt to an array of downstream tasks. However, generally, full fine-tuning is a computationally expensive job. To mitigate this, many techniques have been developed that prime efficiency, a prominent one being Low-Rank Adaptation (LoRA). However, LoRA and its variants employ re-parametrized additive updates. In this paper, we propose Low-Rank Multiplicative Adaptation (LoRMA), which shifts the paradigm of additive updates to a richer space of matrix multiplicative transformations. We tackle challenges such as computational complexity and rank bottleneck of matrix multiplication by effectively re-ordering operations and introducing rank inflation strategies. We conduct extensive experiments to demonstrate the effectiveness of our approach in terms of various evaluation metrics.
Anthology ID:
2025.findings-acl.527
Volume:
Findings of the Association for Computational Linguistics: ACL 2025
Month:
July
Year:
2025
Address:
Vienna, Austria
Editors:
Wanxiang Che, Joyce Nabende, Ekaterina Shutova, Mohammad Taher Pilehvar
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
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Pages:
10113–10133
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URL:
https://preview.aclanthology.org/display_plenaries/2025.findings-acl.527/
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Cite (ACL):
Harsh Bihany, Shubham Patel, and Ashutosh Modi. 2025. LoRMA: Low-Rank Multiplicative Adaptation for LLMs. In Findings of the Association for Computational Linguistics: ACL 2025, pages 10113–10133, Vienna, Austria. Association for Computational Linguistics.
Cite (Informal):
LoRMA: Low-Rank Multiplicative Adaptation for LLMs (Bihany et al., Findings 2025)
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https://preview.aclanthology.org/display_plenaries/2025.findings-acl.527.pdf