Fully Zeroth-Order Bilevel Programming via Gaussian Smoothing
- URL: http://arxiv.org/abs/2404.00158v1
- Date: Fri, 29 Mar 2024 21:12:25 GMT
- Title: Fully Zeroth-Order Bilevel Programming via Gaussian Smoothing
- Authors: Alireza Aghasi, Saeed Ghadimi,
- Abstract summary: We study and analyze zeroth-order approximation algorithms for solving bilvel problems.
To the best of our knowledge, this is the first time that sample bounds are established for a fully zeroth-order bilevel optimization algorithm.
- Score: 7.143879014059895
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: In this paper, we study and analyze zeroth-order stochastic approximation algorithms for solving bilvel problems, when neither the upper/lower objective values, nor their unbiased gradient estimates are available. In particular, exploiting Stein's identity, we first use Gaussian smoothing to estimate first- and second-order partial derivatives of functions with two independent block of variables. We then used these estimates in the framework of a stochastic approximation algorithm for solving bilevel optimization problems and establish its non-asymptotic convergence analysis. To the best of our knowledge, this is the first time that sample complexity bounds are established for a fully stochastic zeroth-order bilevel optimization algorithm.
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