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Related papers: Function-free Optimization via Comparison Oracles

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The goal of this paper is to investigate an approach for derivative-free optimization that has not received sufficient attention in the literature and is yet one of the simplest to implement and parallelize. It consists of computing…

Optimization and Control · Mathematics 2021-02-22 Hao-Jun Michael Shi , Melody Qiming Xuan , Figen Oztoprak , Jorge Nocedal

This paper addresses constrained smooth saddle-point problems in settings where projection onto the feasible sets is computationally expensive. We bridge the gap between projection-based and projection-free optimization by introducing a…

Optimization and Control · Mathematics 2026-04-02 Khanh-Hung Giang-Tran , Soroosh Shafiee , Nam Ho-Nguyen

In this paper, we investigate a class of constrained saddle point (SP) problems where the objective function is nonconvex-concave and smooth. This class of problems has wide applicability in machine learning, including robust multi-class…

Optimization and Control · Mathematics 2023-11-02 Morteza Boroun , Erfan Yazdandoost Hamedani , Afrooz Jalilzadeh

Local optimization presents a promising approach to expensive, high-dimensional black-box optimization by sidestepping the need to globally explore the search space. For objective functions whose gradient cannot be evaluated directly,…

Machine Learning · Computer Science 2023-01-18 Quan Nguyen , Kaiwen Wu , Jacob R. Gardner , Roman Garnett

Arising in semi-parametric statistics, control applications, and as sub-problems in global optimization methods, certain optimization problems can have objective functions requiring numerical integration to evaluate, yet gradient function…

Optimization and Control · Mathematics 2025-03-06 Christian Varner , Vivak Patel

Mathematical optimization is a fundamental tool for decision-making in a wide range of applications. However, in many real-world scenarios, the parameters of the optimization problem are not known a priori and must be predicted from…

Machine Learning · Computer Science 2025-11-13 Senne Berden , Ali İrfan Mahmutoğulları , Dimos Tsouros , Tias Guns

This paper provides lower bounds on the convergence rate of Derivative Free Optimization (DFO) with noisy function evaluations, exposing a fundamental and unavoidable gap between the performance of algorithms with access to gradients and…

Machine Learning · Statistics 2012-09-13 Kevin G. Jamieson , Robert D. Nowak , Benjamin Recht

We analyze combinatorial optimization problems with ordinal, i.e., non-additive, objective functions that assign categories (like good, medium and bad) rather than cost coefficients to the elements of feasible solutions. We review different…

Optimization and Control · Mathematics 2022-04-06 Kathrin Klamroth , Michael Stiglmayr , Julia Sudhoff

When the underlying probability distribution in a stochastic optimization is observed only through data, various data-driven formulations have been studied to obtain approximate optimal solutions. We show that no such formulations can, in a…

Optimization and Control · Mathematics 2021-05-31 Henry Lam

Derivative-free optimization (DFO) is the mathematical study of the optimization algorithms that do not use derivatives. One branch of DFO focuses on model-based DFO methods, where an approximation of the objective function is used to guide…

Numerical Analysis · Mathematics 2016-12-16 Warren Hare

Bilevel optimization minimizes an objective function, defined by an upper-level problem whose feasible region is the solution of a lower-level problem. We study the oracle complexity of finding an $\epsilon$-stationary point with…

Optimization and Control · Mathematics 2025-12-01 Lesi Chen , Jingzhao Zhang

We give a simple and natural method for computing approximately optimal solutions for minimizing a convex function $f$ over a convex set $K$ given by a separation oracle. Our method utilizes the Frank--Wolfe algorithm over the cone of valid…

Optimization and Control · Mathematics 2022-03-14 Daniel Dadush , Christopher Hojny , Sophie Huiberts , Stefan Weltge

One of the most effective algorithms for differentially private learning and optimization is objective perturbation. This technique augments a given optimization problem (e.g. deriving from an ERM problem) with a random linear term, and…

Machine Learning · Computer Science 2021-01-01 Seth Neel , Aaron Roth , Giuseppe Vietri , Zhiwei Steven Wu

Direct alignment methods are increasingly used for aligning large language models (LLMs) with human preferences. However, these methods suffer from the issues of verbosity and likelihood displacement, which can be driven by the noisy…

Computation and Language · Computer Science 2025-10-28 Peter Chen , Xi Chen , Wotao Yin , Tianyi Lin

We study the secure stochastic convex optimization problem. A learner aims to learn the optimal point of a convex function through sequentially querying a (stochastic) gradient oracle. In the meantime, there exists an adversary who aims to…

Machine Learning · Computer Science 2021-04-06 Wei Tang , Chien-Ju Ho , Yang Liu

Recent applications in machine learning have renewed the interest of the community in min-max optimization problems. While gradient-based optimization methods are widely used to solve such problems, there are however many scenarios where…

Optimization and Control · Mathematics 2021-04-15 Sotiris Anagnostidis , Aurelien Lucchi , Youssef Diouane

A very simple first-order algorithm is proposed for solving nonlinear optimization problems with deterministic nonlinear equality constraints. This algorithm adaptively selects steps in the plane tangent to the constraints or steps that…

Optimization and Control · Mathematics 2026-03-11 Serge Gratton , Philippe L. Toint

We consider variants of the classical Frank-Wolfe algorithm for constrained smooth convex minimization, that instead of access to the standard oracle for minimizing a linear function over the feasible set, have access to an oracle that can…

Optimization and Control · Mathematics 2022-02-10 Dan Garber , Noam Wolf

The challenges of black box optimization arise due to imprecise responses and limited output information. This article describes new results on optimizing multivariable functions using an Order Oracle, which provides access only to the…

Optimization and Control · Mathematics 2024-09-20 Boris Chervonenkis , Andrei Krasnov , Alexander Gasnikov , Aleksandr Lobanov

A new algorithm for smooth constrained optimization is proposed that never computes the value of the problem's objective function and that handles both equality and inequality constraints. The algorithm uses an adaptive switching strategy…

Optimization and Control · Mathematics 2026-02-13 S. Bellavia , S. Gratton , B. Morini , Ph. L. Toint