Hansu Gu
Author directory2026
StreamMemBench: Streaming Evaluation of Agent Memory for Future-Oriented Assistance
Guanming Liu | Yuqi Ren | Hansu Gu | Peng Zhang | Weihang Wang | Jiahao Liu | Ning Gu | Tun Lu
Findings of the Association for Computational Linguistics: EMNLP 2026
Guanming Liu | Yuqi Ren | Hansu Gu | Peng Zhang | Weihang Wang | Jiahao Liu | Ning Gu | Tun Lu
Findings of the Association for Computational Linguistics: EMNLP 2026
A central role of personal-agent memory is to turn stored information and prior interactions into future-oriented assistance. In daily use, useful cues come from what the agent observes and how the user interacts with the agent, and the agent must carry them forward from the current request to similar future tasks. Existing memory benchmarks usually test dialogue recall or task improvement in isolation, leaving the trajectory from streaming observations to later assistance largely untested. We introduce StreamMemBench, a streaming benchmark that constructs a two-step task sequence around each evidence anchor from EgoLife egocentric streams. The initial task tests evidence use, while the follow-up task tests whether feedback and interaction experience are reused. Four metrics diagnose evidence recall, initial evidence use, feedback incorporation, and follow-up reuse. Experiments with eight memory systems across two backbones show that current systems often fail to use observed evidence or turn feedback into reliable follow-up behavior, even when evidence is stored or feedback is incorporated locally.
PACEShop: Evaluating Personalized, Actionable, Compositional, and Evidence-grounded Shopping Assistants
Weimin Lyu | Chen Luo | Guangrui Li | Yaochen Xie | Dhineshkumar Ramasubbu | Arief Koesdwiady | Wanqiu Long | Hansu Gu | Yutong Chen | Zheshen Wang | Dakuo Wang | Yi Liu
Findings of the Association for Computational Linguistics: EMNLP 2026
Weimin Lyu | Chen Luo | Guangrui Li | Yaochen Xie | Dhineshkumar Ramasubbu | Arief Koesdwiady | Wanqiu Long | Hansu Gu | Yutong Chen | Zheshen Wang | Dakuo Wang | Yi Liu
Findings of the Association for Computational Linguistics: EMNLP 2026
Shopping assistants are shifting from ranked product lists toward structured decision support, where systems must synthesize shopper context, product evidence, and next-step guidance into a coherent recommendation experience. This changes the unit of evaluation: a fluent response can still fail by ignoring shopper context, contradicting itself across components, or leaving defects too vague to localize. Existing personalization, grounding, and LLM-as-a-judge benchmarks cover pieces of this problem, but they do not define a joint evaluation target for structured shopping-assistant responses. We formulate this missing evaluation target as PACE: Personalized, Actionable, Compositional, and Evidence-grounded evaluation. We instantiate PACE with two artifacts: PACEShop, a benchmark dataset that makes the target measurable through 22,625 controlled records with structured personas, auditable evidence pools, GOOD/BAD labels, and gold defect family and location annotations; and PACEJudge, a training-free judging protocol that makes the target reportable through a structured output contract. Our experiments show that generic judges can recognize broad quality but fail to recover the diagnostic fields required for PACE; PACEShop makes these failures verifiable, and PACEJudge improves persona-source, cross-component, grounding, and family/location closure without retraining, showing that realistic shopping-assistant evaluation requires a task-matched output contract rather than only a stronger backbone or scalar prompt.
VIRA-Bench: Diagnosing Pedagogical Contingency Understanding in Online Tutoring Videos
Weihang Wang | Hansu Gu | Guanming Liu | Peng Zhang | Ning Gu | Tun Lu
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Weihang Wang | Hansu Gu | Guanming Liu | Peng Zhang | Ning Gu | Tun Lu
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Understanding online tutoring requires more than recognizing isolated events. A model must connect what a teacher says or does to how the learner responds and how the teacher subsequently adapts. Existing video benchmarks emphasize event and temporal understanding, while educational-dialogue benchmarks are largely transcript-based, leaving this interactional contingency underexplored. We introduce VIRA-Bench, a diagnostic benchmark for short-horizon pedagogical contingency in one-to-one tutoring videos. Grounded in the Initiation–Response–Follow-up structure and contingent teaching theory, VIRA-Bench contains 1,005 clips and 1,322 multiple-choice questions organized into three layers: Observable Evidence Grounding, Interaction Contingency Reasoning, and Support-Response Modeling. Items are built through researcher-led evidence auditing and expert verification to keep questions tied to observable interaction evidence. Across 11 multimodal large language models, the best model reaches 61.3% accuracy, compared with 91.0% on a stratified human subset, with interaction contingency reasoning emerging as the most consistent weakness. Controlled evidence interventions reveal distinct dependencies across layers. Removing video hurts observable grounding most, while disrupting interaction order hurts contingency reasoning most. Additional controls show that this distinction survives free-response evaluation and cannot be explained by question-option shortcuts or video–transcript misalignment. By separating visual grounding from order-sensitive interaction reasoning, VIRA-Bench exposes diagnostic differences that aggregate video-QA scores obscure.
LLMs for Now, Fine-Tuning for Later: An Ensemble Approach to Data Drift in Domain-Specific Tasks
Yuxuan Lu | Bingsheng Yao | Shao Zhang | Yisi Sang | Yun Wang | Hansu Gu | Peng Zhang | Tun Lu | Toby Jia-Jun Li | Dakuo Wang
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 4: Student Research Workshop)
Yuxuan Lu | Bingsheng Yao | Shao Zhang | Yisi Sang | Yun Wang | Hansu Gu | Peng Zhang | Tun Lu | Toby Jia-Jun Li | Dakuo Wang
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 4: Student Research Workshop)
Deploying machine learning models in real-world domain-specific scenarios is challenged by the scarcity of expert annotations and by data drift, where the statistical properties of incoming data continuously evolve. Active Learning (AL) iteratively improves compact models with expert annotations but suffers from recurring cold-start degradation, while LLMs provide strong off-the-shelf performance yet cannot leverage newly accumulated labels, raising the question: how can we better leverage LLMs to assist the active learning process? Through an empirical study on five legal and biomedical datasets, we reveal a complementary temporal dynamic: LLMs excel during early and post-drift stages, while AL-assisted compact models eventually surpass them as annotations accumulate. Motivated by this finding, we propose an ensemble system that combines an LLM, an AL-assisted compact model, and an automatic switch module that routes predictions to the better-performing model in real time. Evaluated under simulated data drift on two mental health datasets, our system achieves 96–98% switch accuracy and consistently outperforms either model used alone.
2025
Learning with Less: Knowledge Distillation from Large Language Models via Unlabeled Data
Juanhui Li | Sreyashi Nag | Hui Liu | Xianfeng Tang | Sheikh Muhammad Sarwar | Limeng Cui | Hansu Gu | Suhang Wang | Qi He | Jiliang Tang
Findings of the Association for Computational Linguistics: NAACL 2025
Juanhui Li | Sreyashi Nag | Hui Liu | Xianfeng Tang | Sheikh Muhammad Sarwar | Limeng Cui | Hansu Gu | Suhang Wang | Qi He | Jiliang Tang
Findings of the Association for Computational Linguistics: NAACL 2025
In real-world NLP applications, Large Language Models (LLMs) offer promising solutions due to their extensive training on vast datasets. However, the large size and high computation demands of LLMs limit their practicality in many applications, especially when further fine-tuning is required. To address these limitations, smaller models are typically preferred for deployment. However, their training is hindered by the scarcity of labeled data. In contrast, unlabeled data is often readily which can be leveraged by using LLMs to generate pseudo-labels for training smaller models. This enables the smaller models (student) to acquire knowledge from LLMs (teacher) while reducing computational costs. This process introduces challenges, such as potential noisy pseudo-labels. % and the high computational expense of processing large unlabeled datasets. Selecting high-quality and informative data is therefore critical to enhance model performance while improving the efficiency of data utilization. To address this, we propose LLKD that enables Learning with Less computational resources and less data for Knowledge Distillation from LLMs. LLKD is an adaptive sample selection method that incorporates signals from both the teacher and student. Specifically, it prioritizes samples where the teacher demonstrates high confidence in its labeling, indicating reliable labels, and where the student exhibits a high information need, identifying challenging samples that require further learning. Our comprehensive experiments show that LLKD achieves superior performance across various datasets with higher data efficiency.
EcomScriptBench: A Multi-task Benchmark for E-commerce Script Planning via Step-wise Intention-Driven Product Association
Weiqi Wang | Limeng Cui | Xin Liu | Sreyashi Nag | Wenju Xu | Chen Luo | Sheikh Muhammad Sarwar | Yang Li | Hansu Gu | Hui Liu | Changlong Yu | Jiaxin Bai | Yifan Gao | Haiyang Zhang | Qi He | Shuiwang Ji | Yangqiu Song
Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Weiqi Wang | Limeng Cui | Xin Liu | Sreyashi Nag | Wenju Xu | Chen Luo | Sheikh Muhammad Sarwar | Yang Li | Hansu Gu | Hui Liu | Changlong Yu | Jiaxin Bai | Yifan Gao | Haiyang Zhang | Qi He | Shuiwang Ji | Yangqiu Song
Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Goal-oriented script planning, or the ability to devise coherent sequences of actions toward specific goals, is commonly employed by humans to plan for typical activities. In e-commerce, customers increasingly seek LLM-based assistants to generate scripts and recommend products at each step, thereby facilitating convenient and efficient shopping experiences. However, this capability remains underexplored due to several challenges, including the inability of LLMs to simultaneously conduct script planning and product retrieval, difficulties in matching products caused by semantic discrepancies between planned actions and search queries, and a lack of methods and benchmark data for evaluation. In this paper, we step forward by formally defining the task of E-commerce Script Planning (EcomScript) as three sequential subtasks. We propose a novel framework that enables the scalable generation of product-enriched scripts by associating products with each step based on the semantic similarity between the actions and their purchase intentions. By applying our framework to real-world e-commerce data, we construct the very first large-scale EcomScript dataset, EcomScriptBench, which includes 605,229 scripts sourced from 2.4 million products. Human annotations are then conducted to provide gold labels for a sampled subset, forming an evaluation benchmark. Extensive experiments reveal that current (L)LMs face significant challenges with EcomScript tasks, even after fine-tuning, while injecting product purchase intentions improves their performance.
2023
An Intent-based and Annotation-free Method for Duplicate Question Detection in CQA Forums
Yubo Shu | Hansu Gu | Peng Zhang | Tun Lu | Ning Gu
Findings of the Association for Computational Linguistics: EMNLP 2023
Yubo Shu | Hansu Gu | Peng Zhang | Tun Lu | Ning Gu
Findings of the Association for Computational Linguistics: EMNLP 2023
With the advent of large language models (LLMs), Community Question Answering (CQA) forums offer well-curated questions and answers that can be utilized for instruction-tuning, effectively training LLMs to be aligned with human intents. However, the issue of duplicate questions arises as the volume of content within CQA continues to grow, posing a threat to content quality. Recent research highlights the benefits of detecting and eliminating duplicate content. It not only enhances the LLMs’ ability to generalize across diverse intents but also improves the efficiency of training data utilization while addressing concerns related to information leakage. However, existing methods for detecting duplicate questions in CQA typically rely on generic text-pair matching models, overlooking the intent behind the questions. In this paper, we propose a novel intent-based duplication detector named Intent-DQD that comprehensively leverages intent information to address the problem of duplicate question detection in CQA. Intent-DQD first leverages the characteristics in CQA forums and extracts training labels to recognize and match intents without human annotation. Intent-DQD then effectively aggregates intent-level relations and establishes question-level relations to enable intent-aware duplication detection. Experimental results on fifteen distinct domains from both CQADupStack and Stack Overflow datasets demonstrate the effectiveness of Intent-DQD. Reproducible codes and datasets will be released upon publication of the paper.
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Co-authors
- Tun Lu 4
- Ning Gu 3
- Limeng Cui 2
- Qi He 2
- Guanming Liu 2
- Hui Liu 2
- Chen Luo 2
- Sreyashi Nag 2
- Sheikh Muhammad Sarwar 2
- Dakuo Wang 2
- Weihang Wang 2
- Peng Zhang 2
- Peng Zhang 2
- Jiaxin Bai 1
- Yutong Chen 1
- Yifan Gao 1
- Shuiwang Ji 1
- Arief Koesdwiady 1
- Guangrui Li 1
- Juanhui Li 1
- Toby Jia-Jun Li 1
- Yang Li 1
- Jiahao Liu 1
- Xin Liu 1
- Yi Liu 1
- Wanqiu Long 1
- Yuxuan Lu 1
- Weimin Lyu 1
- Dhineshkumar Ramasubbu 1
- Yuqi Ren 1
- Yisi Sang 1
- Yubo Shu 1
- Yangqiu Song 1
- Jiliang Tang 1
- Xianfeng Tang 1
- Suhang Wang 1
- Weiqi Wang 1
- Yun Wang 1
- Zheshen Wang 1
- Yaochen Xie 1
- Wenju Xu 1
- Bingsheng Yao 1
- Changlong Yu 1
- Haiyang Zhang 1
- Shao Zhang 1