Minimisation of Quasar-Convex Functions Using Random Zeroth-Order Oracles

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Farzin, Amir Ali, Pun, Yuen-Man, Braun, Philipp, Shames, Iman
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917235739590656
author Farzin, Amir Ali
Pun, Yuen-Man
Braun, Philipp
Shames, Iman
author_facet Farzin, Amir Ali
Pun, Yuen-Man
Braun, Philipp
Shames, Iman
contents This paper explores the performance of a random Gaussian smoothing zeroth-order (ZO) scheme for minimising quasar-convex (QC) and strongly quasar-convex (SQC) functions in both unconstrained and constrained settings. For the unconstrained problem, we establish the ZO algorithm's convergence to a global minimum along with its complexity when applied to both QC and SQC functions. For the constrained problem, we introduce the new notion of proximal-quasar-convexity and prove analogous results to the unconstrained case. Specifically, we derive complexity bounds and prove convergence of the algorithm to a neighbourhood of a global minimum whose size can be controlled under a variance reduction scheme. Beyond the theoretical guarantees, we demonstrate the practical implications of our results on several machine learning problems where quasar-convexity naturally arises, including linear dynamical system identification and generalised linear models.
format Preprint
id arxiv_https___arxiv_org_abs_2505_02281
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Minimisation of Quasar-Convex Functions Using Random Zeroth-Order Oracles
Farzin, Amir Ali
Pun, Yuen-Man
Braun, Philipp
Shames, Iman
Optimization and Control
Artificial Intelligence
Machine Learning
Numerical Analysis
This paper explores the performance of a random Gaussian smoothing zeroth-order (ZO) scheme for minimising quasar-convex (QC) and strongly quasar-convex (SQC) functions in both unconstrained and constrained settings. For the unconstrained problem, we establish the ZO algorithm's convergence to a global minimum along with its complexity when applied to both QC and SQC functions. For the constrained problem, we introduce the new notion of proximal-quasar-convexity and prove analogous results to the unconstrained case. Specifically, we derive complexity bounds and prove convergence of the algorithm to a neighbourhood of a global minimum whose size can be controlled under a variance reduction scheme. Beyond the theoretical guarantees, we demonstrate the practical implications of our results on several machine learning problems where quasar-convexity naturally arises, including linear dynamical system identification and generalised linear models.
title Minimisation of Quasar-Convex Functions Using Random Zeroth-Order Oracles
topic Optimization and Control
Artificial Intelligence
Machine Learning
Numerical Analysis
url https://arxiv.org/abs/2505.02281