arXiv Machine Learning

Can Entry-Wise Clipping Give Spectral Control of Stochastic Gradients?

arXiv:2605. 27733v2 Announce Type: replace Abstract: Training instabilities such as loss spikes are frequently the result of stochastic gradient noise.

arXiv Machine Learning
Sep 11

Musec: MomentUm SpEctral Clipping for Stable Muon-type Training

Musec introduces MomentUm SpEctral Clipping, an optimizer-level, architecture‑agnostic technique that replaces Muon’s spectral flattening with selective spectral clipping to stabilize training. By clipping singular values above a threshold while preserving the momentum’s spectral structure, Musec addresses loss spikes and unbounded weight growth without requiring architecture‑specific changes. Soft Musec, an efficient implementation using smooth spectral saturation via coupled Newton‑Schulz iterations, offers convergence guarantees in nonconvex nonsmooth stochastic optimization and empirically improves stability across diverse learning rates and model sizes.

By Zhuanghua Liu, Menglian Wang, Luo Luo
arXiv Machine Learning
Oct 16

On the Last-Iterate Convergence of Clipped Gradient Methods

The paper establishes the first optimal last‑iterate convergence rates, in high probability, for Clipped‑SGD when the gradient noise is heavy‑tailed. It addresses the gap left by earlier results that required strong noise assumptions, such as exponentially decaying tails. By proving these rates, the authors provide theoretical support for the practical effectiveness of gradient clipping in stochastic convex optimization.

By Zijian Liu
arXiv Machine Learning
Sep 30

Optimization Risk Bounds for Kolmogorov-Arnold Networks Trained by DP-SGD with Correlated Noise

The paper provides the first optimization risk bounds for two‑layer Kolmogorov‑Arnold Networks (KANs) trained with clipped mini‑batch differentially private stochastic gradient descent (DP‑SGD) that uses temporally correlated noise. The bounds explicitly capture the effects of temporal correlation, clipping, mini‑batch sampling, and network width, and show that correlation can reduce leading noise terms while the clipping threshold influences an effective step size. Experiments on synthetic data and MNIST confirm the theoretical predictions, and the authors extend the results to population risk guarantees via algorithmic stability, recovering several known special cases.

By Puyu Wang, Jan Schuchardt, Nikita Kalinin, Marcio Monteiro, Junyu Zhou, Sophie Fellenz, Christoph Lampert, Marius Kloft
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
arXiv Statistics ML
5d ago

Phases of Muon: When Muon Eclipses SignSGD

The paper analyzes the stochastic optimizer Muon, which orthogonalizes an exponential moving average of minibatch gradients, and compares its behavior to the baseline SignSGD on a high‑dimensional matrix‑valued least squares problem. It derives deterministic dynamics showing Muon’s sensitivity to an effective batch size and its failure to resolve small eigenmodes when whitening is exact and the effective batch is small, while Momentum and finite Newton–Shulz iterations can mitigate this. The study presents a phase diagram in terms of data and target exponents, indicating when Muon or SignSGD is preferable based on covariance spectrum steepness and target loss scaling.

By Elliot Paquette, Noah Marshall, Lucas Benigni, Guangyuan Wang, Atish Agarwala, Courtney Paquette