arXiv Machine Learning

FARO: Function-Space Adaptive Return-to-Risk Optimization via Cross-Block Equal-Risk-Contribution Budget Allocation

The paper introduces FARO, a function‑space adaptive optimizer that treats each parameter block as a decision unit, assigning geometry based on counterfactual return and reallocating budgets via cross‑block equal risk contribution (ERC). On a GPT‑style model trained on FineWeb, FARO‑Adaptive matches the best hand‑designed optimizer (NorMuonAndAdam) while FARO‑ERC further reduces clean‑data loss by an average of 0.0136 nats across six seeds, achieving a robust improvement without extra time or memory. The method works by trimming the riskiest blocks and remains effective even under corrupted data streams.

arXiv Machine Learning
Sep 30

Scaling Zero-Order Pretraining through Model Sharding

arXiv:2609.37899v1 Announce Type: new Abstract: Zero-order optimization (ZO) trains without backpropagation, making it relevant to forward-only hardware and non-differentiable loss, but its gradient...

By Francois Chaubard, Mykel J. Kochenderfer, Chris R\'e
arXiv AI
Jun 29

When Is an LLM Worth It for Hyperparameter Optimization? A Budget-Matched Study on Tabular Data Finds the Warm-Start Is a Default Configuration, Not the Model

arXiv:2606. 21641v2 Announce Type: replace-cross Abstract: Large language models (LLMs) have been proposed as hyperparameter-optimization (HPO) advisors that "warm-start" search from prior knowledge, proposing strong configurations in very few evaluations.

By Carson Rodrigues, Oysturn Vas, Isaiah Abner DCosta, Nithish Kumar Prabhakaran
arXiv Machine Learning
Jul 31

LoRA Scaffolded Policy Optimization (LSPO): A Sampling-Time Low-Rank Scaffold for Recovering Reinforcement-Learning Gradient on Zero-Reward Cliff Prompts

arXiv:2607. 27787v1 Announce Type: new Abstract: Reinforcement learning from verifiable rewards (RLVR) for mathematical reasoning suffers from a structural blind spot: on "cliff" prompts-those on which every sampled rollout in a group fails-the group-normalized advantage is identically zero, so GRPO produces no gradient on precisely the prompts at the frontier of the model's capability.

By Ken Ding
Hugging Face Trending Papers
Jul 30

LoRA Scaffolded Policy Optimization (LSPO): A Sampling-Time Low-Rank Scaffold for Recovering Reinforcement-Learning Gradient on Zero-Reward Cliff Prompts

Reinforcement learning from verifiable rewards (RLVR) for mathematical reasoning suffers from a structural blind spot: on "cliff" prompts-those on which every sampled rollout in a group fails-the group-normalized advantage is identically zero, so GRPO produces no gradient on precisely the prompts at the frontier of the model's capability. We introduce LoRA Scaffolded Policy Optimization (LSPO), a sampling-time mechanism that recovers this lost gradient.

arXiv Machine Learning
1d ago

Adaptive Multi Mode: Budget-Aware Routing of Optimizers By Online Landscape Probes

The paper introduces Adaptive Multi Mode (AMM), a budget‑aware router that selects among several optimization engines—quasi‑Newton, trust‑region, coordinate, multistart, and evolution‑strategy—based on online probes of the problem landscape. Each probe evaluates features such as curvature, plateaus, separability, kinks, basins, and fractal structure, and is assigned a validity range and cost relative to the budget. In extensive pre‑registered tests on the bbob benchmark, AMM achieved the highest target share in 382 of 600 function‑dimension‑budget cells, outperforming up to seven competitors and maintaining strong performance across transformations and constraints.

By Benjamin Jacob Bodner
arXiv AI
Aug 25

A Physical Response-and-Memory Model for Muon Optimization

The paper introduces a physical response-and-memory model for the Muon optimizer, explaining its semi‑orthogonalized momentum update as the maximally dissipative direction under an output‑side safety budget. It treats the weight matrix as a responsive medium with internal stress, showing that momentum corresponds to accumulated stress whose relaxation occurs over multiple timescales—fast and slow. Based on this, the authors propose the Bi‑Maxwell optimizer, which uses a two‑timescale memory kernel and achieves target loss in fewer steps on a public large‑language‑model benchmark.

By Yinze Hu, Hongjun Xiang, Xingao Gong, Hongyu Yu
arXiv Machine Learning
Jul 3

SCAPE: Accurate and Efficient LLM Training with Extreme Sparse Communication

arXiv:2607. 01678v1 Announce Type: new Abstract: Communication increasingly dominates the cost of Large Language Model (LLM) pre-training, especially under data-parallel and sharded training schemes, where gradient synchronization and parameter reconstruction overhead increase with model size and system scale.

By Mingkai Zheng, Junlin Chen, Haotian Xie, Zhao Zhang