Publication Type
Conference Proceeding Article
Version
publishedVersion
Publication Date
4-2026
Abstract
Deep neural networks often exhibit substantial disparities in class-wise accuracy, even when trained on class-balanced data—posing concerns for reliable deployment. While prior efforts have explored empirical remedies, a theoretical understanding of such performance disparities in classification remains limited. In this work, we present Margin Regularization for performance disparity Reduction (MR2 ), a theoretically principled regularization for classification by dynamically adjusting margins in both the logit and representation spaces. Our analysis establishes a margin-based, class-sensitive generalization bound that reveals how per-class feature variability contributes to error, motivating the use of larger margins for “hard” classes. Guided by this insight, MR2 optimizes per-class logit margins proportional to feature spread and penalizes excessive representation margins to enhance intra-class compactness. Experiments on seven datasets—including ImageNet—and diverse pre-trained backbones (MAE, MoCov2, CLIP) demonstrate that our MR2 not only improves overall accuracy but also significantly boosts “hard” class performance without trading off “easy” classes, thus reducing the performance disparity. Codes are available in https://github.com/BeierZhu/MR2.
Keywords
image classification, class-wise performance gap
Discipline
Artificial Intelligence and Robotics | Databases and Information Systems
Research Areas
Intelligent Systems and Optimization
Areas of Excellence
Digital transformation
Publication
Proceedings of the Fourteenth International Conference on Learning Representations (ICLR 2026), Rio de Janeiro, Brazil, April 23-27
First Page
1
Last Page
29
Publisher
ICLR
City or Country
Rio de Janeiro, Brazil
Citation
ZHU, Beier; ZHAO, Kesen; CUI, Jiequan; SUN, Qianru; ZHOU, Yuan; YANG, Xun; and ZHANG, Hanwang.
Reducing class-wise performance disparity via margin regularization. (2026). Proceedings of the Fourteenth International Conference on Learning Representations (ICLR 2026), Rio de Janeiro, Brazil, April 23-27. 1-29.
Available at: https://ink.library.smu.edu.sg/sis_research/11202
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This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Additional URL
https://openreview.net/forum?id=KfjpyOcPQj