Projection-Free Variance Reduction Methods for Stochastic Constrained Multi-Level Compositional Optimization

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Jiang, Wei, Yang, Sifan, Yang, Wenhao, Wang, Yibo, Wan, Yuanyu, Zhang, Lijun
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866913380084744192
author Jiang, Wei
Yang, Sifan
Yang, Wenhao
Wang, Yibo
Wan, Yuanyu
Zhang, Lijun
author_facet Jiang, Wei
Yang, Sifan
Yang, Wenhao
Wang, Yibo
Wan, Yuanyu
Zhang, Lijun
contents This paper investigates projection-free algorithms for stochastic constrained multi-level optimization. In this context, the objective function is a nested composition of several smooth functions, and the decision set is closed and convex. Existing projection-free algorithms for solving this problem suffer from two limitations: 1) they solely focus on the gradient mapping criterion and fail to match the optimal sample complexities in unconstrained settings; 2) their analysis is exclusively applicable to non-convex functions, without considering convex and strongly convex objectives. To address these issues, we introduce novel projection-free variance reduction algorithms and analyze their complexities under different criteria. For gradient mapping, our complexities improve existing results and match the optimal rates for unconstrained problems. For the widely-used Frank-Wolfe gap criterion, we provide theoretical guarantees that align with those for single-level problems. Additionally, by using a stage-wise adaptation, we further obtain complexities for convex and strongly convex functions. Finally, numerical experiments on different tasks demonstrate the effectiveness of our methods.
format Preprint
id arxiv_https___arxiv_org_abs_2406_03787
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Projection-Free Variance Reduction Methods for Stochastic Constrained Multi-Level Compositional Optimization
Jiang, Wei
Yang, Sifan
Yang, Wenhao
Wang, Yibo
Wan, Yuanyu
Zhang, Lijun
Optimization and Control
Machine Learning
This paper investigates projection-free algorithms for stochastic constrained multi-level optimization. In this context, the objective function is a nested composition of several smooth functions, and the decision set is closed and convex. Existing projection-free algorithms for solving this problem suffer from two limitations: 1) they solely focus on the gradient mapping criterion and fail to match the optimal sample complexities in unconstrained settings; 2) their analysis is exclusively applicable to non-convex functions, without considering convex and strongly convex objectives. To address these issues, we introduce novel projection-free variance reduction algorithms and analyze their complexities under different criteria. For gradient mapping, our complexities improve existing results and match the optimal rates for unconstrained problems. For the widely-used Frank-Wolfe gap criterion, we provide theoretical guarantees that align with those for single-level problems. Additionally, by using a stage-wise adaptation, we further obtain complexities for convex and strongly convex functions. Finally, numerical experiments on different tasks demonstrate the effectiveness of our methods.
title Projection-Free Variance Reduction Methods for Stochastic Constrained Multi-Level Compositional Optimization
topic Optimization and Control
Machine Learning
url https://arxiv.org/abs/2406.03787