Zirui He
Author directory2026
HyperPathsRAG: Multi-Target Path Approximation over Hypergraph Knowledge Graphs for Multi-Hop QA
Guanhua Zhu | Zirui He | Mengnan Du | Chenxi Yuan
Findings of the Association for Computational Linguistics: EMNLP 2026
Guanhua Zhu | Zirui He | Mengnan Du | Chenxi Yuan
Findings of the Association for Computational Linguistics: EMNLP 2026
Multi-hop question answering needs evidence that is scattered across many sentences and ordered along a reasoning chain. Existing RAG systems struggle with this setting because flat chunk retrieval can miss bridge facts, binary graph structures lose n-ary information, and unordered top-K contexts leave evidence composition to the answer model. We introduce HyperPathsRAG, a hypergraph-based RAG framework that aligns query decomposition with the corpus index. It decomposes questions into n-ary sub-questions aligned with hypergraph facts, jointly matches all sub-questions to retrieve reasoning paths, scores paths by chain completeness, and presents the retrieved evidence in reasoning order. We evaluate in the candidate-passage setting on the 1k-question hard subsets of HotpotQA, 2Wiki, and MuSiQue, with three answering LLMs. HyperPathsRAG attains the best average Exact Match on every backbone (up to 42.2 EM / 56.2 F1 with Llama-3.3-70B-Instruct), and the best average F1 on two of three backbones; ablations attribute the bulk of the gain to the hypergraph index and the multi-target retriever. Our code is available at https://anonymous.4open.science/r/HyperPathsRAG-AE05/.
SAE-FiRE: Enhancing Earnings Surprise Predictions Through Sparse Autoencoder Feature Selection
Huopu Zhang | Yanguang Liu | Miao Zhang | Zirui He | Mengnan Du
Findings of the Association for Computational Linguistics: ACL 2026
Huopu Zhang | Yanguang Liu | Miao Zhang | Zirui He | Mengnan Du
Findings of the Association for Computational Linguistics: ACL 2026
Predicting earnings surprises through the analysis of earnings conference call transcripts has attracted increasing attention from the financial research community. Conference calls serve as critical communication channels between company executives, analysts, and shareholders, offering valuable forward-looking information. However, these transcripts present significant analytical challenges, typically containing over 5,000 words with substantial redundancy and industry-specific terminology that creates obstacles for language models. In this work, we propose the Sparse Autoencoder for Financial Representation Enhancement (SAE-FiRE) framework to address these limitations by extracting key information while eliminating redundancy. SAE-FiRE employs Sparse Autoencoders (SAEs) to efficiently identify patterns and filter out noises, and focusing specifically on capturing nuanced financial signals that have predictive power for earnings surprises. Experimental results indicate that the proposed method can significantly outperform comparing baselines.
Universal Activation Verbalizer: A Unified Framework for Cross-Model Activation Explanation
Haiyan Zhao | Zirui He | Guanchu Wang | Ali Payani | Yingcong Li | Mengnan Du
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Haiyan Zhao | Zirui He | Guanchu Wang | Ali Payani | Yingcong Li | Mengnan Du
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Activation verbalization explains hidden representations in natural language, but existing methods are mostly limited to self-explanation, where each model explains only its own activations. We introduce Universal Activation Verbalizer (UAV), a shared-decoder framework that uses donor- and layer-specific adapters to explain activations from heterogeneous donor models. UAV learns a lightweight adapter that converts donor activations into soft tokens in decoder’s embedding space, and further supports adapter-only transfer by reusing a frozen decoder-side LoRA while training only a new adapter for another donor. Across classification, fact retrieval, and gist summarization, UAV remains competitive with strong self-explanation baselines while enabling cross-model verbalization across model families and scales. Ablations show that decoder-side tuning mainly improves task behavior, whereas the adapter provides the activation-grounded factual and semantic evidence. Code and data are available at our GitHub repository.
2025
SAE-SSV: Supervised Steering in Sparse Representation Spaces for Reliable Control of Language Models
Zirui He | Mingyu Jin | Bo Shen | Ali Payani | Yongfeng Zhang | Mengnan Du
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Zirui He | Mingyu Jin | Bo Shen | Ali Payani | Yongfeng Zhang | Mengnan Du
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Large language models (LLMs) have demonstrated impressive capabilities in natural language understanding and generation, but controlling their behavior reliably remains challenging, especially in open-ended generation settings. This paper introduces a novel supervised steering approach that operates in sparse, interpretable representation spaces. We employ sparse autoencoders (SAEs) to obtain sparse latent representations that aim to disentangle semantic attributes from model activations. Then we train linear classifiers to identify a small subspace of task-relevant dimensions in latent representations. Finally, we learn supervised steering vectors constrained to this subspace, optimized to align with target behaviors. Experiments across sentiment, truthfulness, and politics polarity steering tasks with multiple LLMs demonstrate that our supervised steering vectors achieve higher success rates with minimal degradation in generation quality compared to existing methods. Further analysis reveals that a notably small subspace is sufficient for effective steering, enabling more targeted and interpretable interventions.
2024
Mitigating Shortcuts in Language Models with Soft Label Encoding
Zirui He | Huiqi Deng | Haiyan Zhao | Ninghao Liu | Mengnan Du
Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024)
Zirui He | Huiqi Deng | Haiyan Zhao | Ninghao Liu | Mengnan Du
Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024)
Recent research has shown that large language models rely on spurious correlations in the data for natural language understanding (NLU) tasks. In this work, we aim to answer the following research question: Can we reduce spurious correlations by modifying the ground truth labels of the training data? Specifically, we propose a simple yet effective debiasing framework, named Soft Label Encoding (SoftLE). First, we train a teacher model to quantify each sample’s degree of relying on shortcuts. Then, we encode this shortcut degree into a dummy class and use it to smooth the original ground truth labels, generating soft labels. These soft labels are used to train a more robust student model that reduces spurious correlations between shortcut features and certain classes. Extensive experiments on two NLU benchmark tasks via two language models demonstrate that SoftLE significantly improves out-of-distribution generalization while maintaining satisfactory in-distribution accuracy. Our code is available at https://github.com/ZiruiHE99/sle