collaborators

11 papers

cs.CV2025

Alchemist: Unlocking Efficiency in Text-to-Image Model Training via Meta-Gradient Data Selection

Kaixin Ding, Yang Zhou, Xi Chen +5

Recent advances in Text-to-Image (T2I) generative models, such as Imagen, Stable Diffusion, and FLUX, have led to remarkable improvements in visual quality. However, their performa…

cs.CV2025

Seg-VAR: Image Segmentation with Visual Autoregressive Modeling

Rongkun Zheng, Lu Qi, Xi Chen +3

While visual autoregressive modeling (VAR) strategies have shed light on image generation with the autoregressive models, their potential for segmentation, a task that requires pre…

cs.LG2025

Stratified GRPO: Handling Structural Heterogeneity in Reinforcement Learning of LLM Search Agents

Mingkang Zhu, Xi Chen, Bei Yu +2

Large language model (LLM) agents increasingly rely on external tools such as search engines to solve complex, multi-step problems, and reinforcement learning (RL) has become a key…

cs.LG2025

From Noisy Traces to Stable Gradients: Bias-Variance Optimized Preference Optimization for Aligning Large Reasoning Models

Mingkang Zhu, Xi Chen, Bei Yu +2

Large reasoning models (LRMs) generate intermediate reasoning traces before producing final answers, yielding strong gains on multi-step and mathematical tasks. Yet aligning LRMs w…

cs.CL2025

Enhancing LLM Knowledge Learning through Generalization

Mingkang Zhu, Xi Chen, Zhongdao Wang +3

As Large language models (LLMs) are increasingly deployed in diverse applications, faithfully integrating evolving factual knowledge into these models remains a critical challenge.…

cs.CV2025

FocalClick-XL: Towards Unified and High-quality Interactive Segmentation

Xi Chen, Hengshuang Zhao

Interactive segmentation enables users to extract binary masks of target objects through simple interactions such as clicks, scribbles, and boxes. However, existing methods often s…