← Search

Guillaume Braun

6 accepted papers

2026

Fast Escape, Slow Convergence: Learning Dynamics of Phase Retrieval under Power-Law Data

ICLR 2026oral

Scaling laws describe how learning performance improves with data, compute, or training time, and have become a central theme in modern deep learning. We study this phenomenon in a canonical nonlinear model: phase retrieval with anisotropic Gaussian inputs whose covariance spectrum follows a power l…

Cited by 0SourceScholar
2026

Spectral Gradient Descent Mitigates Anisotropy-Driven Misalignment: A Case Study in Phase Retrieval

ICML 2026poster

Spectral gradient methods, such as the Muon optimizer, modify gradient updates by preserving directional information while discarding scale, and have shown strong empirical performance in deep learning. We investigate the mechanisms underlying these gains through a dynamical analysis of a nonlinear …

Cited by 0SourceScholar
2025

Learning a Single Index Model from Anisotropic Data with Vanilla Stochastic Gradient Descent

AISTATS 2025poster

We investigate the problem of learning a Single Index Model (SIM)---a popular model for studying the ability of neural networks to learn features---from anisotropic Gaussian inputs by training a neuron using vanilla Stochastic Gradient Descent (SGD). While the isotropic case has been extensively stu…

Cited by 0SourceScholar
2024

VEC-SBM: Optimal Community Detection with Vectorial Edges Covariates

AISTATS 2024poster

Social networks are often associated with rich side information, such as texts and images. While numerous methods have been developed to identify communities from pairwise interactions, they usually ignore such side information. In this work, we study an extension of the Stochastic Block Model (SBM)…

2022

An iterative clustering algorithm for the Contextual Stochastic Block Model with optimality guarantees

ICML 2022spotlight

Real-world networks often come with side information that can help to improve the performance of network analysis tasks such as clustering. Despite a large number of empirical and theoretical studies conducted on network clustering methods during the past decade, the added value of side information…