activity
20242026
collaborators

9 papers

cs.AI2026

Improving Value-based Process Verifier via Low-Cost Variance Reduction

Zetian Sun, Dongfang Li, Baotian Hu +1

Large language models (LLMs) have achieved remarkable success in a wide range of tasks. However, their reasoning capabilities, particularly in complex domains like mathematics, rem…

cs.AI2026

Is On-Policy Data always the Best Choice for Direct Preference Optimization-based LM Alignment?

Zetian Sun, Dongfang Li, Xuhui Chen +2

The alignment of language models~(LMs) with human preferences is critical for building reliable AI systems. The problem is typically framed as optimizing an LM policy to maximize t…

cs.LG2026

Improving Value-based Process Verifier via Structural Prior Injection

Zetian Sun, Dongfang Li, Baotian Hu +2

In the Large Language Model(LLM) reasoning scenario, people often estimate state value via Monte Carlo sampling. Though Monte Carlo estimation is an elegant method with less induct…

cs.CL2025

KaLM-Embedding-V2: Superior Training Techniques and Data Inspire A Versatile Embedding Model

Xinping Zhao, Xinshuo Hu, Zifei Shan +14

Recent advancements in Large Language Models (LLMs)-based text embedding models primarily focus on data scaling or synthesis, yet limited exploration of training techniques and dat…

cs.LG2025

Stabilizing Long-term Multi-turn Reinforcement Learning with Gated Rewards

Zetian Sun, Dongfang Li, Zhuoen Chen +2

Reward sparsity in long-horizon reinforcement learning (RL) tasks remains a significant challenge, while existing outcome-based reward shaping struggles to define meaningful immedi…

cs.IR2025

FunnelRAG: A Coarse-to-Fine Progressive Retrieval Paradigm for RAG

Xinping Zhao, Yan Zhong, Zetian Sun +5

Retrieval-Augmented Generation (RAG) prevails in Large Language Models. It mainly consists of retrieval and generation. The retrieval modules (a.k.a. retrievers) aim to find useful…