arXiv Machine Learning

High-dimensional learning dynamics of multi-pass Stochastic Gradient Descent in multi-index models

The paper presents an asymptotically exact description of the learning dynamics of multi‑pass stochastic gradient descent (SGD) in high‑dimensional non‑convex multi‑index models. By considering sub‑linear batch sizes and a critical learning‑rate scaling, the authors derive a continuous‑time scaling limit governed by dynamical mean‑field equations driven by a scalar Poisson jump process. This framework unifies several existing theories of SGD—gradient flow on empirical risk, autonomous ODEs for online SGD, and diffusion approximations in least‑squares—while revealing distinct behavior for general multi‑pass SGD beyond these special cases.

arXiv Machine Learning
Jul 14

Exact Dynamics of Multi-class Stochastic Gradient Descent

arXiv:2510. 14074v2 Announce Type: replace-cross Abstract: We develop a framework for analyzing the learning dynamics of high-dimensional problems trained using one-pass stochastic gradient descent (SGD) with data from multiple anisotropic classes.

By Elizabeth Collins-Woodfin, Inbar Seroussi
arXiv Machine Learning
Oct 16

Stochastic Gradient Descent: A Nonlinear Time Series Perspective

This paper studies the statistical properties of Stochastic Gradient Descent (SGD) with a constant step size using the framework of iterated random functions. It demonstrates convergence in Euclidean distance via Geometric Moment Contraction, establishes quenched central limit theorems, invariance principles, and α-stable convergence for averaged SGD regardless of initialization, and explores the effect of step sizes through derivative processes. The authors further develop a Richardson-Romberg extrapolation with multiple step sizes, propose a bias-reduced variant, and introduce an online inference method that yields empirical confidence intervals with coverage approaching nominal levels as sample size increases.

By Jiaqi Li, Zhipeng Lou, Stefan Richter, Wei Biao Wu
arXiv Machine Learning
Jul 7

Learning rate adaptive stochastic gradient descent optimization methods: numerical simulations for deep learning methods for partial differential equations and convergence analyses

arXiv:2406. 14340v2 Announce Type: replace-cross Abstract: The standard stochastic gradient descent (SGD) optimization method, as well as adaptive methods such as the Adam optimizer fail to converge if the learning rates do not converge to zero (particularly, in the situation of constant learning rates).

By Steffen Dereich, Arnulf Jentzen, Adrian Riekert
arXiv Statistics ML
Oct 2

Exact information accounting for SGD methods

The paper presents an exact, information‑theoretic analysis of stochastic gradient descent (SGD) and its variants, showing that a preconditioned SGD step corresponds to a posterior‑mean update in a Gaussian Bayes model. It decomposes one‑step regret into an intrinsic‑time cost and a change in comparator information, extending this split to an identity for the objective itself. The framework links convex convergence, saddle‑point escape, flatness‑generalization trade‑offs, learning‑rate schedules, adaptive optimizers, and various SGD variants, and it is validated on synthetic and real training runs, revealing how different optimizers achieve the same training loss through distinct step characteristics.

By Akshay Balsubramani