← Search

Xiaobao Wu

35 accepted papers

2026

Graph-R1: Towards Agentic GraphRAG Framework via End-to-end Reinforcement Learning

ICML 2026poster

Retrieval-Augmented Generation (RAG) mitigates hallucination in LLMs by incorporating external knowledge, but relies on chunk-based retrieval that lacks structural semantics. GraphRAG methods improve RAG by modeling knowledge as entity-relation graphs, but still face challenges in high construction …

Cited by 0SourceScholar
2025

A Comprehensive Survey on Learning from Rewards for Large Language Models: Reward Models and Learning Strategies

EMNLP 2025

Recent developments in Large Language Models (LLMs) have shifted from pre-training scaling to post-training and test-time scaling. Across these developments, a key unified paradigm has arisen: Learning from Rewards, where reward signals act as the guiding stars to steer LLM behavior. It has underpin

Cited by 0SourcePDFScholar
2025

AntiLeakBench: Preventing Data Contamination by Automatically Constructing Benchmarks with Updated Real-World Knowledge

ACL 2025long

Data contamination hinders fair LLM evaluation by introducing test data into newer models’ training sets. Existing studies solve this challenge by updating benchmarks with newly collected data. However, they fail to guarantee contamination-free evaluation as the newly collected data may contain pre-…

2025

Enhancing Multimodal Entity Linking with Jaccard Distance-based Conditional Contrastive Learning and Contextual Visual Augmentation

NAACL 2025long

Previous research on multimodal entity linking (MEL) has primarily employed contrastive learning as the primary objective. However, using the rest of the batch as negative samples without careful consideration, these studies risk leveraging easy features and potentially overlook essential details th…

Cited by 2SourcePDFScholar
2025

Full-Step-DPO: Self-Supervised Preference Optimization with Step-wise Rewards for Mathematical Reasoning

ACL 2025finding

Direct Preference Optimization (DPO) often struggles with long-chain mathematical reasoning. Existing approaches, such as Step-DPO, typically improve this by focusing on the first erroneous step in the reasoning chain. However, they overlook all other steps and rely heavily on humans or GPT-4 to ide…

2025

HyperGraphRAG: Retrieval-Augmented Generation via Hypergraph-Structured Knowledge Representation

NeurIPS 2025poster

Standard Retrieval-Augmented Generation (RAG) relies on chunk-based retrieval, whereas GraphRAG advances this approach by graph-based knowledge representation. However, existing graph-based RAG approaches are constrained by binary relations, as each edge in an ordinary graph connects only two entiti…

Cited by 0SourceScholar
2025

KBQA-o1: Agentic Knowledge Base Question Answering with Monte Carlo Tree Search

ICML 2025poster

Knowledge Base Question Answering (KBQA) aims to answer natural language questions with a large-scale structured knowledge base (KB). Despite advancements with large language models (LLMs), KBQA still faces challenges in weak KB awareness, imbalance between effectiveness and efficiency, and high rel…

2025

MRAG: A Modular Retrieval Framework for Time-Sensitive Question Answering

EMNLP 2025

Understanding temporal concepts and answering time-sensitive questions is crucial yet a challenging task for question-answering systems powered by large language models (LLMs). Existing approaches either update the parametric knowledge of LLMs with new facts, which is resource-intensive and often im

2025

Motion-aware Contrastive Learning for Temporal Panoptic Scene Graph Generation

AAAI 2025technical

To equip artificial intelligence with a comprehensive understanding towards a temporal world, video and 4D panoptic scene graph generation abstracts visual data into nodes to represent entities and edges to capture temporal relations. Existing methods encode entity masks tracked across temporal dime…

Cited by 2SourcePDFScholar
2025

Multi-Scale Contrastive Learning for Video Temporal Grounding

AAAI 2025technical

Temporal grounding, which localizes video moments related to a natural language query, is a core problem of vision-language learning and video understanding. To encode video moments of varying lengths, recent methods employ a multi-level structure known as a feature pyramid. In this structure, lower…

Cited by 1SourcePDFScholar
2025

RuleArena: A Benchmark for Rule-Guided Reasoning with LLMs in Real-World Scenarios

ACL 2025long

This paper introduces RuleArena, a novel and challenging benchmark designed to evaluate the ability of large language models (LLMs) to follow complex, real-world rules in reasoning. Covering three practical domains – airline baggage fees, NBA transactions, and tax regulations – RuleArena assesses LL…

2025

SCOPE: Compress Mathematical Reasoning Steps for Efficient Automated Process Annotation

ACL 2025finding

Process Reward Models (PRMs) have demonstrated promising results in mathematical reasoning, but existing process annotation approaches, whether through human annotations or Monte Carlo simulations, remain computationally expensive. In this paper, we introduce Step COmpression for Process Estimation…

2025

Towards Storage-Efficient Visual Document Retrieval: An Empirical Study on Reducing Patch-Level Embeddings

ACL 2025finding

Despite the strong performance of ColPali/ColQwen2 in Visualized Document Retrieval (VDR), its patch-level embedding approach leads to excessive memory usage. This empirical study investigates methods to reduce patch embeddings per page while minimizing performance degradation. We evaluate two token…

2025

Unlearning Backdoor Attacks for LLMs with Weak-to-Strong Knowledge Distillation

ACL 2025finding

Parameter-efficient fine-tuning (PEFT) can bridge the gap between large language models (LLMs) and downstream tasks. However, PEFT has been proven vulnerable to malicious attacks. Research indicates that poisoned LLMs, even after PEFT, retain the capability to activate internalized backdoors when in…

2025

Zero-to-Strong Generalization: Eliciting Strong Capabilities of Large Language Models Iteratively without Gold Labels

COLING 2025main

Large Language Models (LLMs) have demonstrated remarkable performance through supervised fine-tuning or in-context learning using gold labels. However, this paradigm is limited by the availability of gold labels, while in certain scenarios, LLMs may need to perform tasks that are too complex for hum…

Cited by 3SourcePDFScholar
2024

Encoding and Controlling Global Semantics for Long-form Video Question Answering

EMNLP 2024main

Seeking answers effectively for long videos is essential to build video question answering (videoQA) systems. Previous methods adaptively select frames and regions from long videos to save computations. However, this fails to reason over the whole sequence of video, leading to sub-optimal performanc…

2024

FASTopic: Pretrained Transformer is a Fast, Adaptive, Stable, and Transferable Topic Model

NeurIPS 2024poster

Topic models have been evolving rapidly over the years, from conventional to recent neural models. However, existing topic models generally struggle with either effectiveness, efficiency, or stability, highly impeding their practical applications. In this paper, we propose FASTopic, a fast, adaptive…

Cited by 6SourcePDFScholar
2024

KDMCSE: Knowledge Distillation Multimodal Sentence Embeddings with Adaptive Angular margin Contrastive Learning

NAACL 2024long

Previous work on multimodal sentence embedding has proposed multimodal contrastive learning and achieved promising results. However, by taking the rest of the batch as negative samples without reviewing when forming contrastive pairs, those studies encountered many suspicious and noisy negative exam…

2024

Meta-optimized Angular Margin Contrastive Framework for Video-Language Representation Learning

ECCV 2024poster

"Data quality stands at the forefront of deciding the effectiveness of video-language representation learning. However, video-text pairs in previous data typically do not align perfectly with each other, which might lead to video-language representations that do not accurately reflect cross-modal se…

Cited by 8SourcePDFScholar
2024

Modeling Dynamic Topics in Chain-Free Fashion by Evolution-Tracking Contrastive Learning and Unassociated Word Exclusion

ACL 2024findings

Dynamic topic models track the evolution of topics in sequential documents, which have derived various applications like trend analysis. However, existing models suffer from repetitive topic and unassociated topic issues, failing to reveal the evolution and hindering further applications. To address…

2024

On the Affinity, Rationality, and Diversity of Hierarchical Topic Modeling

AAAI 2024technical

Hierarchical topic modeling aims to discover latent topics from a corpus and organize them into a hierarchy to understand documents with desirable semantic granularity. However, existing work struggles with producing topic hierarchies of low affinity, rationality, and diversity, which hampers docume…

2024

READ-PVLA: Recurrent Adapter with Partial Video-Language Alignment for Parameter-Efficient Transfer Learning in Low-Resource Video-Language Modeling

AAAI 2024technical

Fully fine-tuning pretrained large-scale transformer models has become a popular paradigm for video-language modeling tasks, such as temporal language grounding and video-language summarization. With a growing number of tasks and limited training data, such full fine-tuning approach leads to costly…

Cited by 7SourcePDFScholar
2024

Topic Modeling as Multi-Objective Contrastive Optimization

ICLR 2024poster

Recent representation learning approaches enhance neural topic models by optimizing the weighted linear combination of the evidence lower bound (ELBO) of the log-likelihood and the contrastive learning objective that contrasts pairs of input documents. However, document-level contrastive learning mi…

Cited by 7SourcePDFScholar
2024

Towards the TopMost: A Topic Modeling System Toolkit

ACL 2024system demonstrations

Topic models have a rich history with various applications and have recently been reinvigorated by neural topic modeling. However, these numerous topic models adopt totally distinct datasets, implementations, and evaluations. This impedes quick utilization and fair comparisons, and thereby hinders t…

2023

DemaFormer: Damped Exponential Moving Average Transformer with Energy-Based Modeling for Temporal Language Grounding

EMNLP 2023long findings

Temporal Language Grounding seeks to localize video moments that semantically correspond to a natural language query. Recent advances employ the attention mechanism to learn the relations between video moments and the text query. However, naive attention might not be able to appropriately capture su…

Cited by 0SourceScholar
2023

Effective Neural Topic Modeling with Embedding Clustering Regularization

ICML 2023poster

Topic models have been prevalent for decades with various applications. However, existing topic models commonly suffer from the notorious topic collapsing: discovered topics semantically collapse towards each other, leading to highly repetitive topics, insufficient topic discovery, and damaged model…

2023

Fact-Checking Complex Claims with Program-Guided Reasoning

ACL 2023long

Fact-checking real-world claims often requires collecting multiple pieces of evidence and applying complex multi-step reasoning. In this paper, we present Program-Guided Fact-Checking (ProgramFC), a novel fact-checking model that decomposes complex claims into simpler sub-tasks that can be solved us…

2023

Gradient-Boosted Decision Tree for Listwise Context Model in Multimodal Review Helpfulness Prediction

ACL 2023findings

Multimodal Review Helpfulness Prediction (MRHP) aims to rank product reviews based on predicted helpfulness scores and has been widely applied in e-commerce via presenting customers with useful reviews. Previous studies commonly employ fully-connected neural networks (FCNNs) as the final score predi…

2023

InfoCTM: A Mutual Information Maximization Perspective of Cross-Lingual Topic Modeling

AAAI 2023technical

Cross-lingual topic models have been prevalent for cross-lingual text analysis by revealing aligned latent topics. However, most existing methods suffer from producing repetitive topics that hinder further analysis and performance decline caused by low-coverage dictionaries. In this paper, we propos…

2023

Zero-Shot Text Classification via Self-Supervised Tuning

ACL 2023findings

Existing solutions to zero-shot text classification either conduct prompting with pre-trained language models, which is sensitive to the choices of templates, or rely on large-scale annotated data of relevant tasks for meta-tuning. In this work, we propose a new paradigm based on self-supervised lea…

2022

Adaptive Contrastive Learning on Multimodal Transformer for Review Helpfulness Prediction

EMNLP 2022main

Modern Review Helpfulness Prediction systems are dependent upon multiple modalities, typically texts and images. Unfortunately, those contemporary approaches pay scarce attention to polish representations of cross-modal relations and tend to suffer from inferior optimization. This might cause harm t…

Cited by 25SourcePDFScholar
2022

Mitigating Data Sparsity for Short Text Topic Modeling by Topic-Semantic Contrastive Learning

EMNLP 2022main

To overcome the data sparsity issue in short text topic modeling, existing methods commonly rely on data augmentation or the data characteristic of short texts to introduce more word co-occurrence information. However, most of them do not make full use of the augmented data or the data characteristi…