The paper presents a learning-to-optimize (L2O) framework that injects summable perturbations into Krasnosel'skii-Mann iterations to accelerate solving fixed-point problems with nonexpansive mappings. It proves that, under metric sub-regularity, the parametrized iterations achieve local linear convergence with a vanishing bias and include all fast-converging iterations. The framework is applied to enhance operator splitting methods, such as Douglas‑Rachford, and is validated on a best‑approximation problem.
By Andrea Martin, Giuseppe Belgioioso
arXiv:2509. 14969v2 Announce Type: replace Abstract: We introduce a new adaptive step-size strategy for convex optimization with stochastic gradient that exploits the local geometry of the objective function only by means of a first-order stochastic oracle and without any hyper-parameter tuning.
By Jean-Fran\c{c}ois Aujol, J\'er\'emie Bigot, Camille Castera
The paper introduces Row-wise Matrix AdaGrad and Column-wise Matrix AdaGrad, two adaptive subgradient methods that extend AdaGrad to matrix-valued parameters by using row-wise and column-wise proximal functions. It presents a general Online Mirror Descent framework that derives these optimizers through online regret minimization, providing regret guarantees that can be tighter than entry-wise AdaGrad for structured gradients. Experiments on matrix factorization and deep neural-network training show that aligning adaptive scaling with matrix structure improves optimization stability, allows larger learning rates, and supports greater network depth.
By Wenpeng Zhang, Runsheng Yu, Peilin Zhao
arXiv:2601.13519v4 Announce Type: replace-cross
Abstract: This paper introduces a new problem-dependent regret measure for online convex optimization with smooth losses. The notion, which we call the...
By Wenzhi Gao, Chang He, Madeleine Udell
arXiv:2606. 21528v2 Announce Type: replace-cross Abstract: We study first-order methods for solving monotone variational inequalities arising in min-max optimization.
By Motahareh Sohrabi, Jianxin You, Simon Lacoste-Julien, Eduard Gorbunov, Gauthier Gidel
arXiv:2602.08372v2 Announce Type: replace
Abstract: We study dynamic regret minimization in non-stationary online learning, with a primary focus on follow-the-regularized-leader (FTRL) methods. FTRL...
By Yan-Feng Xie, Yu-Jie Zhang, Peng Zhao, Zhi-Hua Zhou