Ran Xu 0002

dblp:71/1270-2 · DBLP profile ↗
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17ranked-venue papers
7as first author
17since 2021 · last 2026
0000-0002-2189-0386ORCID · conflict

Domains — the database's venue-derived domains; a paper can count in several

Artificial intelligence and machine learning · 14 · 6 first-author · 14 since 2021Databases, data management, data science and information retrieval · 6 · 2 first-author · 6 since 2021Applied, interdisciplinary, general and emerging computing · 2 · 2 since 2021Graphics, computer vision, multimedia, augmented reality and games · 1 · 1 first-author · 1 since 2021
YearPublicationVenuePosition
2026 OpenRubrics: Towards Scalable Synthetic Rubric Generation for Reward Modeling and LLM Alignment
abstract
Reward modeling lies at the core of reinforcement learning from human feedback (RLHF), yet most existing reward models rely on scalar or pairwise judgments that fail to capture the multifaceted nature of human preferences.Recent studies have explored rubrics-as-rewards (RaR) that uses structured criteria to capture multiple dimensions of response quality.However, producing rubrics that are both reliable and scalable remains a key challenge.In this work, we introduce OpenRubrics, a diverse, large-scale collection of (prompt, rubric) pairs for training rubric-generation and rubric-based reward models.To elicit discriminative and comprehensive evaluation signals, we introduce Contrastive Rubric Generation (CRG), which derives both hard rules (explicit constraints) and principles (implicit qualities) by contrasting preferred and rejected responses.We further remove noisy rubrics via preserving preference-label consistency.Across multiple reward-modeling benchmarks, our rubricbased reward model, RUBRIC-RM, surpasses strong size-matched baselines by 8.4%.These gains transfer to policy models on instructionfollowing and biomedical benchmarks.The model weights and datasets are publicly available at https://huggingface.co/OpenRubrics.* These authors contributed equally to this work, order was determined randomly (by rolling a die).
Tianci Liu 0003, Ran Xu 0002, Tony Yu, Ilgee Hong, Carl Yang 0001, Tuo Zhao, Haoyu Wang 0004
ACL (1)2
2025 Retrieval-augmented GUI Agents with Generative Guidelines
abstract
GUI agents powered by vision-language models (VLMs) show promise in automating complex digital tasks.However, their effectiveness in real-world applications is often limited by scarce training data and the inherent complexity of these tasks, which frequently require longtailed knowledge covering rare, unseen scenarios.We propose RAG-GUI , a lightweight VLM that leverages web tutorials at inference time.RAG-GUI is first warm-started via supervised finetuning (SFT) and further refined through self-guided rejection sampling finetuning (RSF).Designed to be model-agnostic, RAG-GUI functions as a generic plug-in that enhances any VLM-based agent.Evaluated across three distinct tasks, it consistently outperforms baseline agents and surpasses other inference baselines by 2.6% to 13.3% across two model sizes, demonstrating strong generalization and practical plug-and-play capabilities in real-world scenarios.
Ran Xu 0002, Kaixin Ma, Wenhao Yu 0002, Hongming Zhang 0009, Joyce C. Ho, Carl Yang 0001, Dong Yu 0001
EMNLP1
2025 A Survey on Unifying Large Language Models and Knowledge Graphs for Biomedicine and Healthcare
abstract
In recent years, the landscape of digital biomedicine and healthcare has been reshaped due to the disruptive breakthroughs in AIfacilitated by tremendous data and high-performance computers, large language models (LLMs) have transformed information technology from accessing data to performing analytical tasks.While demonstrating unprecedented capabilities, LLMs have been found unreliable in tasks requiring factual knowledge and rigorous reasoning.Biomedicine and healthcare, as an important vertical domain rapidly benefitting from progress in AI, necessitates strict requirements on the accuracy, controllability, and interpretability of analytical models, posing critical challenges for LLMs.Despite recent studies addressing the hallucination problem of LLMs, research on empowering LLMs with the ability to plan, reason, and ground with explicit knowledge has also started to prosper, especially in the biomedicine and healthcare domain.On the other hand, biomedical data are enormous and notoriously complex, coming from various sources (e.g., biomedical knowledge bases, online literature, and hospitals) and bearing various modalities (e.g., tables, texts, images and time-series).Healthcare professionals have spent decades collecting, cleaning, and curating various types of data.The processes are extremely costly, producing various datasets with different data schemas, coding systems, and quality standards, many privately
Ran Xu 0002, Patrick Jiang, Linhao Luo, Cao Xiao, Adam R. Cross, Shirui Pan, Jimeng Sun 0001, Carl Yang 0001
KDD (2)1
2025 SimRAG: Self-Improving Retrieval-Augmented Generation for Adapting Large Language Models to Specialized Domains
abstract
Ran Xu, Hui Liu, Sreyashi Nag, Zhenwei Dai, Yaochen Xie, Xianfeng Tang, Chen Luo, Yang Li, Joyce C. Ho, Carl Yang, Qi He. Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers). 2025.
Ran Xu 0002, Hui Liu 0033, Sreyashi Nag, Zhenwei Dai, Yaochen Xie, Xianfeng Tang, Chen Luo 0003, Yang Li 0055, Joyce C. Ho, Carl Yang 0001, Qi He 0002
NAACL (Long Papers)1
2025 AceSearcher: Bootstrapping Reasoning and Search for LLMs via Reinforced Self-Play
abstract
Search-augmented LLMs often struggle with complex reasoning tasks due to ineffective multi-hop retrieval and limited reasoning ability. We propose AceSearcher, a cooperative self-play framework that trains a single large language model (LLM) to alternate between two roles: a decomposer that breaks down complex queries and a solver that integrates retrieved contexts for answer generation. AceSearcher couples supervised fine-tuning on a diverse mixture of search, reasoning, and decomposition tasks with reinforcement fine-tuning optimized for final answer accuracy, eliminating the need for intermediate annotations. Extensive experiments on three reasoning-intensive tasks across 10 datasets show that AceSearcher outperforms state-of-the-art baselines, achieving an average exact match improvement of 7.6%. Remarkably, on document-level finance reasoning tasks, AceSearcher-32B matches the performance of the giant DeepSeek-V3 model using less than 5% of iits parameters. Even at smaller scales (1.5B and 8B), AceSearcher often surpasses existing search-augmented LLMs with up to 9× more parameters, highlighting its exceptional efficiency and effectiveness in tackling complex reasoning tasks.
Ran Xu 0002, Yuchen Zhuang, Zihan Dong, Yue Yu 0001, Joyce C. Ho, Linjun Zhang, Haoyu Wang 0003, Wenqi Shi 0002, Carl Yang 0001
NeurIPS1
2025 HypKG: Hypergraph-Based Knowledge Graph Contextualization for Precision Healthcare
Yuzhang Xie, Ran Xu 0002, Xiao Hu 0002, Jiaying Lu 0001, Carl Yang 0001
ISWC (1)3
2025 A review on knowledge graphs for healthcare: Resources, applications, and promises
Hejie Cui, Jiaying Lu 0001, Ran Xu 0002, Shiyu Wang 0002, Wenjing Ma, Yue Yu 0001, Shaojun Yu, Xuan Kan, Chen Ling 0003, Liang Zhao 0002, Zhaohui S. Qin, Joyce C. Ho, Tianfan Fu, Jing Ma 0005, Mengdi Huai, Carl Yang 0001
J. Biomed. Informatics3
2024 BMRetriever: Tuning Large Language Models as Better Biomedical Text Retrievers
abstract
Developing effective biomedical retrieval models is important for excelling at knowledge-intensive biomedical tasks but still challenging due to the lack of sufficient publicly annotated biomedical data and computational resources. We present BMRetriever, a series of dense retrievers for enhancing biomedical retrieval via unsupervised pre-training on large biomedical corpora, followed by instruction fine-tuning on a combination of labeled datasets and synthetic pairs. Experiments on 5 biomedical tasks across 11 datasets verify BMRetriever's efficacy on various biomedical applications. BMRetriever also exhibits strong parameter efficiency, with the 410M variant outperforming baselines up to 11.7 times larger, and the 2B variant matching the performance of models with over 5B parameters. The training data and model checkpoints are released at https://huggingface.co/BMRetriever to ensure transparency, reproducibility, and application to new domains.
Ran Xu 0002, Wenqi Shi 0002, Yue Yu 0001, Yuchen Zhuang, Yanqiao Zhu 0001, May D. Wang, Joyce C. Ho, Chao Zhang 0014, Carl Yang 0001
EMNLP1
2024 MedAdapter: Efficient Test-Time Adaptation of Large Language Models Towards Medical Reasoning
abstract
Despite their improved capabilities in generation and reasoning, adapting large language models (LLMs) to the biomedical domain remains challenging due to their immense size and privacy concerns. In this study, we propose MedAdapter, a unified post-hoc adapter for test-time adaptation of LLMs towards biomedical applications. Instead of fine-tuning the entire LLM, MedAdapter effectively adapts the original model by fine-tuning only a small BERT-sized adapter to rank candidate solutions generated by LLMs. Experiments on four biomedical tasks across eight datasets demonstrate that MedAdapter effectively adapts both white-box and black-box LLMs in biomedical reasoning, achieving average performance improvements of 18.24% and 10.96%, respectively, without requiring extensive computational resources or sharing data with third parties. MedAdapter also yields enhanced performance when combined with train-time adaptation, highlighting a flexible and complementary solution to existing adaptation methods. Faced with the challenges of balancing model performance, computational resources, and data privacy, MedAdapter provides an efficient, privacy-preserving, cost-effective, and transparent solution for adapting LLMs to the biomedical domain.
Wenqi Shi 0002, Ran Xu 0002, Yuchen Zhuang, Yue Yu 0001, Carl Yang 0001, May D. Wang
EMNLP2
2024 EHRAgent: Code Empowers Large Language Models for Few-shot Complex Tabular Reasoning on Electronic Health Records
abstract
Clinicians often rely on data engineers to retrieve complex patient information from electronic health record (EHR) systems, a process that is both inefficient and time-consuming. We propose EHRAgent, a large language model (LLM) agent empowered with accumulative domain knowledge and robust coding capability. EHRAgent enables autonomous code generation and execution to facilitate clinicians in directly interacting with EHRs using natural language. Specifically, we formulate a multi-tabular reasoning task based on EHRs as a tool-use planning process, efficiently decomposing a complex task into a sequence of manageable actions with external toolsets. We first inject relevant medical information to enable EHRAgent to effectively reason about the given query, identifying and extracting the required records from the appropriate tables. By integrating interactive coding and execution feedback, EHRAgent then effectively learns from error messages and iteratively improves its originally generated code. Experiments on three real-world EHR datasets show that EHRAgent outperforms the strongest baseline by up to 29.6% in success rate, verifying its strong capacity to tackle complex clinical tasks with minimal demonstrations.
Wenqi Shi 0002, Ran Xu 0002, Yuchen Zhuang, Yue Yu 0001, Jieyu Zhang 0001, Yuanda Zhu, Joyce C. Ho, Carl Yang 0001, May D. Wang
EMNLP2
2024 TACCO: Task-guided Co-clustering of Clinical Concepts and Patient Visits for Disease Subtyping based on EHR Data
abstract
The growing availability of well-organized Electronic Health Records (EHR) data has enabled the development of various machine learning models towards disease risk prediction. However, existing risk prediction methods overlook the heterogeneity of complex diseases, failing to model the potential disease subtypes regarding their corresponding patient visits and clinical concept subgroups. In this work, we introduce TACCO, a novel framework that jointly discovers clusters of clinical concepts and patient visits based on a hypergraph modeling of EHR data. Specifically, we develop a novel self-supervised co-clustering framework that can be guided by the risk prediction task of specific diseases. Furthermore, we enhance the hypergraph model of EHR data with textual embeddings and enforce the alignment between the clusters of clinical concepts and patient visits through a contrastive objective. Comprehensive experiments conducted on the public MIMIC-III dataset and Emory internal CRADLE dataset over the downstream clinical tasks of phenotype classification and cardiovascular risk prediction demonstrate an average 31.25% performance improvement compared to traditional ML baselines and a 5.26% improvement on top of the vanilla hypergraph model without our co-clustering mechanism. In-depth model analysis, clustering results analysis, and clinical case studies further validate the improved utilities and insightful interpretations delivered by TACCO. Code is available at https://github.com/PericlesHat/TACCO.
Hejie Cui, Ran Xu 0002, Yuzhang Xie, Joyce C. Ho, Carl Yang 0001
KDD3
2023 Neighborhood-Regularized Self-Training for Learning with Few Labels
abstract
Training deep neural networks (DNNs) with limited supervision has been a popular research topic as it can significantly alleviate the annotation burden. Self-training has been successfully applied in semi-supervised learning tasks, but one drawback of self-training is that it is vulnerable to the label noise from incorrect pseudo labels. Inspired by the fact that samples with similar labels tend to share similar representations, we develop a neighborhood-based sample selection approach to tackle the issue of noisy pseudo labels. We further stabilize self-training via aggregating the predictions from different rounds during sample selection. Experiments on eight tasks show that our proposed method outperforms the strongest self-training baseline with 1.83% and 2.51% performance gain for text and graph datasets on average. Our further analysis demonstrates that our proposed data selection strategy reduces the noise of pseudo labels by 36.8% and saves 57.3% of the time when compared with the best baseline. Our code and appendices will be uploaded to https://github.com/ritaranx/NeST.
Ran Xu 0002, Yue Yu 0001, Hejie Cui, Xuan Kan, Yanqiao Zhu 0001, Joyce C. Ho, Chao Zhang 0014, Carl Yang 0001
AAAI1
2023 Cold-Start Data Selection for Better Few-shot Language Model Fine-tuning: A Prompt-based Uncertainty Propagation Approach
abstract
We present PATRON, a prompt-based data selection method for pre-trained language model fine-tuning under cold-start scenarios, i.e., no initial labeled data are available. In PATRON, we design (1) a prompt-based uncertainty propagation approach to estimate the importance of data points and (2) a partition-then-rewrite (PTR) strategy to promote sample diversity when querying for annotations. Experiments on six text classification datasets show that PATRON outperforms the strongest cold-start data selection baselines by up to 6.9%. Besides, with 128 labels only, PATRON achieves 91.0% and 92.1% of the fully supervised performance based on vanilla fine-tuning and prompt-based learning respectively. Our implementation of PATRON will be published upon acceptance.
Yue Yu 0001, Rongzhi Zhang, Ran Xu 0002, Jieyu Zhang 0001, Chao Zhang 0014
ACL (1)3
2023 R-Mixup: Riemannian Mixup for Biological Networks
abstract
Biological networks are commonly used in biomedical and healthcare domains to effectively model the structure of complex biological systems with interactions linking biological entities. However, due to their characteristics of high dimensionality and low sample size, directly applying deep learning models on biological networks usually faces severe overfitting. In this work, we propose R-MIXUP, a Mixup-based data augmentation technique that suits the symmetric positive definite (SPD) property of adjacency matrices from biological networks with optimized training efficiency. The interpolation process in R-MIXUP leverages the log-Euclidean distance metrics from the Riemannian manifold, effectively addressing the swelling effect and arbitrarily incorrect label issues of vanilla Mixup. We demonstrate the effectiveness of R-MIXUP with five real-world biological network datasets on both regression and classification tasks. Besides, we derive a commonly ignored necessary condition for identifying the SPD matrices of biological networks and empirically study its influence on the model performance. The code implementation can be found in Appendix E.
Xuan Kan, Zimu Li, Hejie Cui, Yue Yu 0001, Ran Xu 0002, Shaojun Yu, Ying Guo 0003, Carl Yang 0001
KDD5
2023 Open Visual Knowledge Extraction via Relation-Oriented Multimodality Model Prompting
abstract
Images contain rich relational knowledge that can help machines understand the world. Existing methods on visual knowledge extraction often rely on the pre-defined format (e.g., sub-verb-obj tuples) or vocabulary (e.g., relation types), restricting the expressiveness of the extracted knowledge. In this work, we take a first exploration to a new paradigm of open visual knowledge extraction. To achieve this, we present OpenVik which consists of an open relational region detector to detect regions potentially containing relational knowledge and a visual knowledge generator that generates format-free knowledge by prompting the large multimodality model with the detected region of interest. We also explore two data enhancement techniques for diversifying the generated format-free visual knowledge. Extensive knowledge quality evaluations highlight the correctness and uniqueness of the extracted open visual knowledge by OpenVik. Moreover, integrating our extracted knowledge across various visual reasoning applications shows consistent improvements, indicating the real-world applicability of OpenVik.
Hejie Cui, Xinyu Fang, Ran Xu 0002, Xuan Kan, Xin Liu 0039, Yue Yu 0001, Manling Li, Yangqiu Song, Carl Yang 0001
NeurIPS4
2023 Weakly-Supervised Scientific Document Classification via Retrieval-Augmented Multi-Stage Training
abstract
Scientific document classification is a critical task for a wide range of applications, but the cost of collecting human-labeled data can be prohibitive. We study scientific document classification using label names only. In scientific domains, label names often include domain-specific concepts that may not appear in the document corpus, making it difficult to match labels and documents precisely. To tackle this issue, we propose WanDeR, which leverages dense retrieval to perform matching in the embedding space to capture the semantics of label names. We further design the label name expansion module to enrich its representations. Lastly, a self-training step is used to refine the predictions. The experiments on three datasets show that WanDeR outperforms the best baseline by 11.9%. Our code will be published at https://github.com/ritaranx/wander.
Ran Xu 0002, Yue Yu 0001, Joyce C. Ho, Carl Yang 0001
SIGIR1
2022 Learning Task-Aware Effective Brain Connectivity for fMRI Analysis with Graph Neural Networks (Extended Abstract)
abstract
Functional magnetic resonance imaging (fMRI) has become one of the most common imaging modalities for brain function analysis. Recently, graph neural networks (GNN) have been adopted for fMRI analysis with superior performance. Unfortunately, traditional functional brain networks are mainly constructed based on similarities among region of interests (ROI), which are noisy and agnostic to the downstream prediction tasks and can lead to inferior results for GNN-based models. To better adapt GNNs for fMRI analysis, we propose TBDS, an end-to-end framework based on Task-aware Brain connectivity DAG (short for Directed Acyclic Graph) Structure generation for fMRI analysis. The key component of TBDS is the brain network generator which adopts a DAG learning approach to transform the raw time-series into task-aware brain connectivities. Besides, we design an additional contrastive regularization to inject task-specific knowledge during the brain network generation process. Comprehensive experiments on two fMRI datasets, namely Adolescent Brain Cognitive Development (ABCD) and Philadelphia Neuroimaging Cohort (PNC) datasets demonstrate the efficacy of TBDS. In addition, the generated brain networks also highlight the prediction-related brain regions and thus provide unique interpretations of the prediction results. Our implementation will be published upon acceptance.
Yue Yu 0001, Xuan Kan, Hejie Cui, Ran Xu 0002, Yujia Zheng 0001, Xiangchen Song, Yanqiao Zhu 0001, Kun Zhang 0001, Razieh Nabi, Ying Guo 0003, Chao Zhang 0014, Carl Yang 0001
IEEE Big Data4