collaborators

6 papers

math.OC2025

Zeroth-Order Methods for Stochastic Nonconvex Nonsmooth Composite Optimization

Ziyi Chen, Peiran Yu, Heng Huang

This work aims to solve a stochastic nonconvex nonsmooth composite optimization problem. Previous works on composite optimization problem requires the major part to satisfy Lipschi…

cs.LG2025

Provably Mitigating Corruption, Overoptimization, and Verbosity Simultaneously in Offline and Online RLHF/DPO Alignment

Ziyi Chen, Junyi Li, Peiran Yu +1

Reinforcement learning from human feedback (RLHF) and direct preference optimization (DPO) are important techniques to align large language models (LLM) with human preference. Howe…

cs.LG2025

Cost-Aware Contrastive Routing for LLMs

Reza Shirkavand, Shangqian Gao, Peiran Yu +1

We study cost-aware routing for large language models across diverse and dynamic pools of models. Existing approaches often overlook prompt-specific context, rely on expensive mode…

cs.LG2025

Revisiting Convergence: Shuffling Complexity Beyond Lipschitz Smoothness

Qi He, Peiran Yu, Ziyi Chen +1

Shuffling-type gradient methods are favored in practice for their simplicity and rapid empirical performance. Despite extensive development of convergence guarantees under various…

cs.LG2025

Bilevel ZOFO: Efficient LLM Fine-Tuning and Meta-Training

Reza Shirkavand, Peiran Yu, Qi He +1

Fine-tuning pre-trained Large Language Models (LLMs) for downstream tasks using First-Order (FO) optimizers presents significant computational challenges. Parameter-Efficient Fine-…

cs.LG2024

Efficient Fine-Tuning and Concept Suppression for Pruned Diffusion Models

Reza Shirkavand, Peiran Yu, Shangqian Gao +3

Recent advances in diffusion generative models have yielded remarkable progress. While the quality of generated content continues to improve, these models have grown considerably i…