arXiv Machine Learning

Many Optimizers But Only One Training Path: Repeated Resampling for Adaptive Optimizer Selection

The paper introduces Repeated Optimizer Resampling (ROR), a method that treats optimizer choice as a hyperparameter and searches for the best optimizer during a single training run. ROR periodically scouts each candidate optimizer for a short number of epochs, then continues training with the best scout, allowing the optimizer to change over time. Experiments on MNIST, Fashion‑MNIST, and motor insurance claim‑count models show that one‑epoch ROR uses only 24–35% of the training effort required to exhaustively evaluate all optimizers while achieving comparable performance.

arXiv AI
Aug 24

Share the Judge, Learn the Deferral: Where Specialization Helps LLM Evaluation

The paper investigates two strategies for improving large language model (LLM) evaluation: specialized judge weights and rule‑based deferral policies. Experiments on nearly 100,000 rubric‑conditioned samples show that correct rubrics boost accuracy, while incorrect ones hurt it, and that splitting training data into criterion‑specific experts can severely degrade performance unless the experts are warm‑started from a unified model. The authors demonstrate that lightweight deferral cascades can match or exceed the accuracy of larger standalone judges at a fraction of the compute cost, and they provide practical design rules for building efficient, reliable LLM evaluators.

By Ye Chen, Weining Zhang
arXiv Machine Learning
Aug 31

Blog: Survey of Optimizers

The article surveys recent neural‑network optimizers, noting that the field has moved beyond simple Adam variants to encompass matrix‑ and layer‑level designs, time‑policy horizons, and state representations that survive sharding and low‑precision computation. It categorizes optimizers along four axes—temporal estimation, update geometry, horizon management, and representation & systems—highlighting methods such as Muon, Shampoo, SOAP, and quantized states. The survey concludes that while matrix‑aware methods are a genuine advance, no single optimizer universally replaces AdamW, and performance depends on model scale, data‑to‑parameter ratio, batch size, schedule, partitioning, tuning budget, and target metric.

By Ruoran Xu
arXiv Machine Learning
Aug 27

Why and When Neural Networks Improve Local Approximation in Optimization

The paper investigates why neural network surrogates sometimes improve and sometimes worsen derivative‑free optimisation performance. It identifies three key factors—role (whether the surrogate proposes candidates or replaces gradients), radius (the neighbourhood within which a local model is reliable), and room (whether the base method can still progress)—that determine when a learned local model is beneficial. Experiments on 117 benchmark instances show that providing surrogate‑approved candidates boosts success rates, while replacing gradients or ignoring the radius can reduce them.

By Chengkuo Bian, Pengcheng Xie
arXiv AI
1d ago

OptiSelect: How does the Optimizer Shape Data Curriculum?

OptiSelect is a framework that incorporates the optimizer’s effect into online data selection for large language model pretraining. The study shows that optimizers like Lion and Muon, which use sign-based or polar-tangential preconditioners, suffer from a discriminability collapse that limits selection gains, whereas diagonal‑adaptive optimizers such as AdamW and Sophia can achieve higher gains. Experiments on 124M and 720M models confirm the theory and demonstrate that OptiSelect remains effective even when data is rephrased.

By Simin Fan, Alireza Abdollahpoorrostam, Martin Jaggi
arXiv Machine Learning
Sep 7

Optimizer Memory Schedules for Outscaling the Overtraining Axis

The paper studies how different optimizers perform as training duration (overtraining) increases, focusing on matrix‑preconditioned methods (Muon, SOAP) and a momentum‑scheduled method (ADANA) compared to AdamW. Across models ranging from 51M to 253M parameters and overtraining factors up to 256×, the authors find that optimal learning‑rate schedules, weight‑decay coefficients, and memory settings shift with horizon, and that ADANA consistently outperforms AdamW, especially with log‑time weight decay and momentum cooldown. Muon and SOAP maintain roughly constant token‑efficiency advantages, with SOAP potentially improving at the highest overtraining levels.

By Katie Everett, Shikai Qiu
arXiv Machine Learning
3d ago

LESS: Lightweight Evolutionary Supernet Search in Minutes

LESS (Lightweight Evolutionary Supernet Search) is a data‑driven NAS method that uses a brief hard‑path warm‑up and CMA‑ES to evaluate candidate architectures as decoded hard genotypes after six supernet updates. On NAS‑Bench‑201, LESS attains 93.189 % CIFAR‑10 accuracy in just 409.1 seconds, nearly matching FairNAS while using only about 1/24 of its search time. The approach also transfers well to CIFAR‑100, ImageNet16‑120, and the larger DARTS space, achieving high accuracies with searches completed in roughly 43.5 minutes on a single GPU.

By Aviral Gandhi, Jinglue Xu, Jialong Li, Hitoshi Iba
Hugging Face Trending Papers
Jun 10

Finding Sparse Subnetworks in One Training Cycle via Progressive Magnitude-Based Pruning

Neural network pruning reduces model size by removing less important parameters while aiming to preserve predictive performance. Although the Lottery Ticket Hypothesis (LTH) shows that sparse subnetworks can match dense networks when trained from suitable initializations, its iterative pruning procedure requires multiple complete training cycles.