Keywords: Bilevel Optimization, Hyperparameter Optimization, Nonsmooth Optimization
TL;DR: We propose a first-order algorithm based on penalty methods for bilevel hyperparameter selection problems.
Abstract: Hyperparameter optimization (HO) is essential in machine learning and can be structured as a bilevel optimization. However, many existing algorithms designed for addressing nonsmooth lower-level problems involve solving sequential subproblems with high complexity. To tackle this challenge, we introduce penalty methods for solving HO based on strong duality between the lower level problem and its dual. We illustrate that the penalized problem closely approximates the optimal solutions of the original HO under certain conditions. In many real applications, the penalized problem is a weakly-convex objective with proximal-friendly constraints. Furthermore, we develop two fully first-order algorithms to solve the penalized problems. Theoretically, we prove the convergence of the proposed algorithms. We demonstrate the efficiency and superiority of our method across numerical experiments.
Supplementary Material: pdf
Primary Area: optimization
Code Of Ethics: I acknowledge that I and all co-authors of this work have read and commit to adhering to the ICLR Code of Ethics.
Submission Guidelines: I certify that this submission complies with the submission instructions as described on https://iclr.cc/Conferences/2025/AuthorGuide.
Reciprocal Reviewing: I understand the reciprocal reviewing requirement as described on https://iclr.cc/Conferences/2025/CallForPapers. If none of the authors are registered as a reviewer, it may result in a desk rejection at the discretion of the program chairs. To request an exception, please complete this form at https://forms.gle/Huojr6VjkFxiQsUp6.
Anonymous Url: I certify that there is no URL (e.g., github page) that could be used to find authors’ identity.
No Acknowledgement Section: I certify that there is no acknowledgement section in this submission for double blind review.
Submission Number: 3763
Loading