An Adaptive Algorithm for Bilevel Optimization on Riemannian Manifolds

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Shi, Xu, Xiao, Rufeng, Jiang, Rujun
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911204996284416
author Shi, Xu
Xiao, Rufeng
Jiang, Rujun
author_facet Shi, Xu
Xiao, Rufeng
Jiang, Rujun
contents Existing methods for solving Riemannian bilevel optimization (RBO) problems require prior knowledge of the problem's first- and second-order information and curvature parameter of the Riemannian manifold to determine step sizes, which poses practical limitations when these parameters are unknown or computationally infeasible to obtain. In this paper, we introduce the Adaptive Riemannian Hypergradient Descent (AdaRHD) algorithm for solving RBO problems. To our knowledge, AdaRHD is the first method to incorporate a fully adaptive step size strategy that eliminates the need for problem-specific parameters in RBO. We prove that AdaRHD achieves an $\mathcal{O}(1/ε)$ iteration complexity for finding an $ε$-stationary point, thus matching the complexity of existing non-adaptive methods. Furthermore, we demonstrate that substituting exponential mappings with retraction mappings maintains the same complexity bound. Experiments demonstrate that AdaRHD achieves comparable performance to existing non-adaptive approaches while exhibiting greater robustness.
format Preprint
id arxiv_https___arxiv_org_abs_2504_06042
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle An Adaptive Algorithm for Bilevel Optimization on Riemannian Manifolds
Shi, Xu
Xiao, Rufeng
Jiang, Rujun
Optimization and Control
Existing methods for solving Riemannian bilevel optimization (RBO) problems require prior knowledge of the problem's first- and second-order information and curvature parameter of the Riemannian manifold to determine step sizes, which poses practical limitations when these parameters are unknown or computationally infeasible to obtain. In this paper, we introduce the Adaptive Riemannian Hypergradient Descent (AdaRHD) algorithm for solving RBO problems. To our knowledge, AdaRHD is the first method to incorporate a fully adaptive step size strategy that eliminates the need for problem-specific parameters in RBO. We prove that AdaRHD achieves an $\mathcal{O}(1/ε)$ iteration complexity for finding an $ε$-stationary point, thus matching the complexity of existing non-adaptive methods. Furthermore, we demonstrate that substituting exponential mappings with retraction mappings maintains the same complexity bound. Experiments demonstrate that AdaRHD achieves comparable performance to existing non-adaptive approaches while exhibiting greater robustness.
title An Adaptive Algorithm for Bilevel Optimization on Riemannian Manifolds
topic Optimization and Control
url https://arxiv.org/abs/2504.06042