activity
20232026
most citedOptimal Embedding Dimension for Sparse Subspace Embeddings

6 citations · 9 across the 23 of their papers we have counts for

collaborators

25 papers

cs.LG2026

How AI settled the complexity of the oldest SGD algorithm

Michał Dereziński, Xiaoyu Dong

In 1937, Stefan Kaczmarz proposed a simple algorithm for solving systems of linear equations. This algorithm turned out to be the earliest known example of stochastic gradient desc…

math.NA2026

Towards Universal Convergence of Backward Error in Linear System Solvers

Michał Dereziński, Yuji Nakatsukasa, Elizaveta Rebrova

The quest for an algorithm that solves an linear system in time complexity, or when solving up to relative error, is a long-stand…

cs.LG2026

Perfect Parallelization in Mini-Batch SGD with Classical Momentum Acceleration

Sachin Garg, Michał Dereziński

Accelerating stochastic gradient methods with classical momentum schemes, such as Polyak's heavy ball, has proven highly successful in training large-scale machine learning models,…

math.NA2026

Numerical Instabilities in the Kaczmarz Method and Stabilization by Iterative Refinement

Michał Dereziński, Ethan N. Epperly, Deanna Needell +1

The randomized Kaczmarz method and its accelerated variants are a powerful class of iterative methods for solving large-scale linear systems, offering guaranteed convergence with l…

math.NA2026

Accelerating Power Method with Fast Sketching for Stronger Low-Rank Approximation

Shabarish Chenakkod, Michał Dereziński

The power method is one of the most fundamental tools for extracting top principal components from data through low-rank matrix approximation. Yet, when the target rank is large, t…

cs.DS2026

Well-Conditioned Oblivious Perturbations in Linear Space

Shabarish Chenakkod, Michał Dereziński, Xiaoyu Dong +1

Perturbing a deterministic -dimensional matrix with small Gaussian noise is a cornerstone of smoothed analysis of algorithms [Spielman and Teng, JACM 2004], as it reduces the co…

cs.LG2026

Last-Iterate Convergence of Randomized Kaczmarz and SGD with Greedy Step Size

Michał Dereziński, Xiaoyu Dong

We study last-iterate convergence of SGD with greedy step size over smooth quadratics in the interpolation regime, a setting which captures the classical Randomized Kaczmarz algori…

math.NA2026

Linear Systems and Eigenvalue Problems: Open Questions from a Simons Workshop

Noah Amsel, Yves Baumann, Paul Beckman +33

This document presents a series of open questions arising in matrix computations, i.e., the numerical solution of linear algebra problems. It is a result of working groups at the w…

cs.DS2026

The matrix-vector complexity of

Michał Dereziński, Ethan N. Epperly, Raphael A. Meyer

Matrix--vector algorithms, particularly Krylov subspace methods, are widely viewed as the most effective algorithms for solving large systems of linear equations. This paper establ…

cs.DS2025

Optimal Subspace Embeddings: Resolving Nelson-Nguyen Conjecture Up to Sub-Polylogarithmic Factors

Shabarish Chenakkod, Michał Dereziński, Xiaoyu Dong

We give a proof of the conjecture of Nelson and Nguyen [FOCS 2013] on the optimal dimension and sparsity of oblivious subspace embeddings, up to sub-polylogarithmic factors: For an…

cs.DS2025

Faster Low-Rank Approximation and Kernel Ridge Regression via the Block-Nyström Method

Sachin Garg, Michał Dereziński

The Nyström method is a popular low-rank approximation technique for large matrices that arise in kernel methods and convex optimization. Yet, when the data exhibits heavy-tailed s…

cs.DS2025

Approaching Optimality for Solving Dense Linear Systems with Low-Rank Structure

Michał Dereziński, Aaron Sidford

We provide new high-accuracy randomized algorithms for solving linear systems and regression problems that are well-conditioned except for large singular values. For solving su…

cs.LG2025

Turbocharging Gaussian Process Inference with Approximate Sketch-and-Project

Pratik Rathore, Zachary Frangella, Sachin Garg +3

Gaussian processes (GPs) play an essential role in biostatistics, scientific machine learning, and Bayesian optimization for their ability to provide probabilistic predictions and…

math.NA2025★ 1 cited

Randomized Kaczmarz Methods with Beyond-Krylov Convergence

Michał Dereziński, Deanna Needell, Elizaveta Rebrova +1

Randomized Kaczmarz methods form a family of linear system solvers which converge by repeatedly projecting their iterates onto randomly sampled equations. While effective in some c…

cs.DS2024

Optimal Oblivious Subspace Embeddings with Near-optimal Sparsity

Shabarish Chenakkod, Michał Dereziński, Xiaoyu Dong

An oblivious subspace embedding is a random matrix such that, for any -dimensional subspace, with high probability preserves the norms of all vectors in that…

cs.LG2024★ 1 cited

Have ASkotch: A Neat Solution for Large-scale Kernel Ridge Regression

Pratik Rathore, Zachary Frangella, Jiaming Yang +2

Kernel ridge regression (KRR) is a fundamental computational tool, appearing in problems that range from computational chemistry to health analytics, with a particular interest due…

cs.LG2024

Recent and Upcoming Developments in Randomized Numerical Linear Algebra for Machine Learning

Michał Dereziński, Michael W. Mahoney

Large matrices arise in many machine learning and data analysis applications, including as representations of datasets, graphs, model weights, and first and second-order derivative…

math.OC2024

Stochastic Newton Proximal Extragradient Method

Ruichen Jiang, Michał Dereziński, Aryan Mokhtari

Stochastic second-order methods achieve fast local convergence in strongly convex optimization by using noisy Hessian estimates to precondition the gradient. However, these methods…

cs.DS2024

Distributed Least Squares in Small Space via Sketching and Bias Reduction

Sachin Garg, Kevin Tan, Michał Dereziński

Matrix sketching is a powerful tool for reducing the size of large data matrices. Yet there are fundamental limitations to this size reduction when we want to recover an accurate e…

cs.DS2024

Faster Linear Systems and Matrix Norm Approximation via Multi-level Sketched Preconditioning

Michał Dereziński, Christopher Musco, Jiaming Yang

We present a new class of preconditioned iterative methods for solving linear systems of the form . Our methods are based on constructing a low-rank Nyström approximation t…

cs.DS2024

Fine-grained Analysis and Faster Algorithms for Iteratively Solving Linear Systems

Michał Dereziński, Daniel LeJeune, Deanna Needell +1

Despite being a key bottleneck in many machine learning tasks, the cost of solving large linear systems has proven challenging to quantify due to problem-dependent quantities such…

math.OC2024

Second-order Information Promotes Mini-Batch Robustness in Variance-Reduced Gradients

Sachin Garg, Albert S. Berahas, Michał Dereziński

We show that, for finite-sum minimization problems, incorporating partial second-order information of the objective function can dramatically improve the robustness to mini-batch s…

cs.LG2024

HERTA: A High-Efficiency and Rigorous Training Algorithm for Unfolded Graph Neural Networks

Yongyi Yang, Jiaming Yang, Wei Hu +1

As a variant of Graph Neural Networks (GNNs), Unfolded GNNs offer enhanced interpretability and flexibility over traditional designs. Nevertheless, they still suffer from scalabili…

cs.DS2023★ 1 cited

Solving Dense Linear Systems Faster Than via Preconditioning

Michał Dereziński, Jiaming Yang

We give a stochastic optimization algorithm that solves a dense real-valued linear system , returning such that in time: $…