Gradient descent for deep equilibrium single-index models

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Dandapanthula, Sanjit, Ramdas, Aaditya
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908756586004480
author Dandapanthula, Sanjit
Ramdas, Aaditya
author_facet Dandapanthula, Sanjit
Ramdas, Aaditya
contents Deep equilibrium models (DEQs) have recently emerged as a powerful paradigm for training infinitely deep weight-tied neural networks that achieve state of the art performance across many modern machine learning tasks. Despite their practical success, theoretically understanding the gradient descent dynamics for training DEQs remains an area of active research. In this work, we rigorously study the gradient descent dynamics for DEQs in the simple setting of linear models and single-index models, filling several gaps in the literature. We prove a conservation law for linear DEQs which implies that the parameters remain trapped on spheres during training and use this property to show that gradient flow remains well-conditioned for all time. We then prove linear convergence of gradient descent to a global minimizer for linear DEQs and deep equilibrium single-index models under appropriate initialization and with a sufficiently small step size. Finally, we validate our theoretical findings through experiments.
format Preprint
id arxiv_https___arxiv_org_abs_2511_16976
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Gradient descent for deep equilibrium single-index models
Dandapanthula, Sanjit
Ramdas, Aaditya
Machine Learning
Statistics Theory
Deep equilibrium models (DEQs) have recently emerged as a powerful paradigm for training infinitely deep weight-tied neural networks that achieve state of the art performance across many modern machine learning tasks. Despite their practical success, theoretically understanding the gradient descent dynamics for training DEQs remains an area of active research. In this work, we rigorously study the gradient descent dynamics for DEQs in the simple setting of linear models and single-index models, filling several gaps in the literature. We prove a conservation law for linear DEQs which implies that the parameters remain trapped on spheres during training and use this property to show that gradient flow remains well-conditioned for all time. We then prove linear convergence of gradient descent to a global minimizer for linear DEQs and deep equilibrium single-index models under appropriate initialization and with a sufficiently small step size. Finally, we validate our theoretical findings through experiments.
title Gradient descent for deep equilibrium single-index models
topic Machine Learning
Statistics Theory
url https://arxiv.org/abs/2511.16976