collaborators

5 papers

cs.LG2026

Position: Zeroth-Order Optimization in Deep Learning Is Underexplored, Not Underpowered

Sijia Liu, Yicheng Lang, Soumyadeep Pal +6

Zeroth-order (ZO) optimization, learning from finite differences of function evaluations without backpropagation, has recently regained attention in deep learning due to its memory…

cs.LG2026

Downgrade to Upgrade: Optimizer Simplification Enhances Robustness in LLM Unlearning

Yicheng Lang, Yihua Zhang, Chongyu Fan +3

Large language model (LLM) unlearning aims to surgically remove the influence of undesired data or knowledge from an existing model while preserving its utility on unrelated tasks.…

cs.LG2026

Subspace Control: Turning Constrained Model Steering into Controllable Spectral Optimization

Yancheng Huang, Changsheng Wang, Chongyu Fan +7

Foundation models, such as large language models (LLMs), are powerful but often require customization before deployment to satisfy practical constraints such as safety, privacy, an…

cs.LG2026

Powering Up Zeroth-Order Training via Subspace Gradient Orthogonalization

Yicheng Lang, Changsheng Wang, Yihua Zhang +4

Zeroth-order (ZO) optimization provides a gradient-free alternative to first-order (FO) methods by estimating gradients via finite differences of function evaluations, and has rece…

cs.LG2025

Beyond Single-Value Metrics: Evaluating and Enhancing LLM Unlearning with Cognitive Diagnosis

Yicheng Lang, Kehan Guo, Yue Huang +5

Due to the widespread use of LLMs and the rising critical ethical and safety concerns, LLM unlearning methods have been developed to remove harmful knowledge and undesirable capabi…