EDGE: Enhanced Debiased Gradient Extraction for Robust Fine-tuning

Jinglong Li, Kun Zhang, Chenyu Zou, Wei Shi, Xin Li, Si Wei


Abstract
"Recent advances in large-scale pre-training have substantially enhanced the robustness and generalization capabilities of foundation models (e.g., Qwen3 and Llama-4). However, when fine-tuning them on downstream tasks, these models often latch onto dataset-specific biases, learning spurious correlations tied to easy-to-learn but non-robust features. This undermines their performance under distribution shifts, despite strong in-distribution (ID) accuracy. Existing fine-tuning methods, including full-parameter and parameter-efficient techniques, primarily optimize for ID performance and largely overlook out-of-distribution (OOD) robustness. Meanwhile, debiasing has been explored in full fine-tuning, while debiasing strategies on Parameter-Efficient Fine-Tuning (PEFT) remain underexplored. To this end, in this paper, we propose Enhanced Debiased Gradient Extraction (EDGE), a lightweight gradient projection-based method that explicitly suppresses bias-amplifying updates during fine-tuning process. EDGE is a model-agnostic, and plug-and-play debiasing method that operates without relying on predefined bias types or labels.It seamlessly integrates with both full and parameter-efficient fine-tuning, and generalizes acrossNLP and vision tasks. Experiments on synthetic and real-world benchmarks demonstrate thatEDGE effectively reduces bias and consistently improves OOD generalization, offering a unified and practical framework for robust adaptation under dataset bias."
Anthology ID:
2025.ccl-1.68
Volume:
Proceedings of the 24th China National Conference on Computational Linguistics (CCL 2025)
Month:
August
Year:
2025
Address:
Jinan, China
Editors:
Maosong Sun, Peiyong Duan, Zhiyuan Liu, Ruifeng Xu, Weiwei Sun
Venue:
CCL
SIG:
Publisher:
Chinese Information Processing Society of China
Note:
Pages:
890–903
Language:
URL:
https://preview.aclanthology.org/ingest-ccl/2025.ccl-1.68/
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Cite (ACL):
Jinglong Li, Kun Zhang, Chenyu Zou, Wei Shi, Xin Li, and Si Wei. 2025. EDGE: Enhanced Debiased Gradient Extraction for Robust Fine-tuning. In Proceedings of the 24th China National Conference on Computational Linguistics (CCL 2025), pages 890–903, Jinan, China. Chinese Information Processing Society of China.
Cite (Informal):
EDGE: Enhanced Debiased Gradient Extraction for Robust Fine-tuning (Li et al., CCL 2025)
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https://preview.aclanthology.org/ingest-ccl/2025.ccl-1.68.pdf