activity
20242026
collaborators

6 papers

math.NA2026

Debiasing Random Oblique Projections for Subsampled OLS and Fast CUR in High Dimensions

Chengmei Niu, Sachin Garg, Michał Dereziński +1

Random sampling is a fundamental tool in modern machine learning and numerical linear algebra for reducing the computational cost of large-scale matrix problems. Existing analyses,…

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,…

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.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…

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…

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…