Balancing Knowledge Breadth and Task Depth for Effective Domain Adaptation Fine-Tuning

Mu Zhang, Yuxiang Chu, Guangya Yu, Yongqi Fan, Weiyan Zhang, Hang Hu, Tong Ruan, Jingping Liu


Abstract
Training large language models for domain adaptation poses a significant challenge in balancing the acquisition of domain knowledge with the retention of general abilities, often leading to catastrophic forgetting. While curriculum learning offers a promising direction, conventional methods typically rely on a single dimension of knowledge or task, which is insufficient to navigate the trade-off between knowledge breadth and task depth. In this paper, we propose a two-dimensional curriculum learning framework that coordinates model training along two orthogonal axes: the knowledge dimension and the task dimension. We first reconstruct the dataset by clustering instances according to their semantic similarity to general-domain data, and subsequently annotate them with a task hierarchy. Then, we design an integrated curriculum that develops from general to domain-specific knowledge clusters, and within each cluster, from lower- to higher-order cognitive tasks. Compared with the second-best method, our method improves accuracy on medical evaluations by 2.49% and on financial evaluations by 1.2%. Ablation and cross-domain experiments further demonstrate our method as a scalable and effective framework for structured domain adaptation in large language model fine-tuning. We have released the code in an anonymous repository at https://github.com/Melo-1017/Balancing-Knowledge-Breadth-and-Task-Depth.
Anthology ID:
2026.findings-acl.405
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
8287–8304
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.405/
DOI:
Bibkey:
Cite (ACL):
Mu Zhang, Yuxiang Chu, Guangya Yu, Yongqi Fan, Weiyan Zhang, Hang Hu, Tong Ruan, and Jingping Liu. 2026. Balancing Knowledge Breadth and Task Depth for Effective Domain Adaptation Fine-Tuning. In Findings of the Association for Computational Linguistics: ACL 2026, pages 8287–8304, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Balancing Knowledge Breadth and Task Depth for Effective Domain Adaptation Fine-Tuning (Zhang et al., Findings 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.405.pdf
Checklist:
 2026.findings-acl.405.checklist.pdf