Gang Chen

Other people with similar names: Gang Chen , Gang Chen


2025

pdf bib
Aligning Large Language Models to Follow Instructions and Hallucinate Less via Effective Data Filtering
Shuzheng Si | Haozhe Zhao | Gang Chen | Cheng Gao | Yuzhuo Bai | Zhitong Wang | Kaikai An | Kangyang Luo | Chen Qian | Fanchao Qi | Baobao Chang | Maosong Sun
Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

Training LLMs on data containing unfamiliar knowledge during the instruction tuning stage can encourage hallucinations. To address this challenge, we introduce NOVA, a novel framework designed to identify high-quality data that aligns well with the LLM’s learned knowledge to reduce hallucinations. NOVA includes Internal Consistency Probing (ICP) and Semantic Equivalence Identification (SEI) to measure how familiar the LLM is with instruction data. Specifically, ICP evaluates the LLM’s understanding of the given instruction by calculating the tailored consistency among multiple self-generated responses. SEI further assesses the familiarity of the LLM with the target response by comparing it to the generated responses, using the proposed semantic clustering and well-designed voting strategy. Finally, to ensure the quality of selected samples, we introduce an expert-aligned reward model, considering characteristics beyond just familiarity. By considering data quality and avoiding unfamiliar data, we can utilize the selected data to effectively align LLMs to follow instructions and hallucinate less. Experiments show that NOVA significantly reduces hallucinations while maintaining a competitive ability to follow instructions.

pdf bib
GATEAU: Selecting Influential Samples for Long Context Alignment
Shuzheng Si | Haozhe Zhao | Gang Chen | Yunshui Li | Kangyang Luo | Chuancheng Lv | Kaikai An | Fanchao Qi | Baobao Chang | Maosong Sun
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing

Aligning large language models to handle instructions with extremely long contexts has yet to be fully investigated. Previous studies have attempted to scale up the available data volume by synthesizing long instruction-following samples, as constructing such a dataset tends to be challenging for annotators. However, a lack of a well-defined strategy for ensuring data quality may introduce low-quality samples and restrict the model’s performance. Thus, we propose GATEAU, a novel framework to address the unique challenge of long context alignment by identifying the influential samples enriched with long-range dependency relations. Specifically, GATEAU measures the long-range dependencies from two essential aspects: the difficulty of generating target responses due to the long-range dependencies, and the difficulty of understanding long inputs due to such dependencies. Comprehensive experiments indicate that GATEAU effectively identifies influential samples and the model trained on these selected samples exhibits better instruction-following and long-context understanding capabilities.

2024

pdf bib
HyperLoRA: Efficient Cross-task Generalization via Constrained Low-Rank Adapters Generation
Chuancheng Lv | Lei Li | Shitou Zhang | Gang Chen | Fanchao Qi | Ningyu Zhang | Hai-Tao Zheng
Findings of the Association for Computational Linguistics: EMNLP 2024

Adapting pre-trained language models (PLMs) for cross-task generalization is a crucial research area within the field of NLP. While fine-tuning and in-context learning are effective approaches for adapting LMs to emerging tasks, they can be costly and inefficient. Recently, some researchers have focused on achieving efficient task adaptation via hypernetwork, which is a meta network that generates task-specific weights based on task-oriented information without any optimization. However, the training of hypernetworks often lacks stability since the optimization signal is not straightforward, and the task information is not adequately representative. Moreover, previous works train hypenetworks with the general corpus, which is struggling with few-shot adaptation. To address these issues, we introduce HyperLoRA, a hypernetwork for LoRA parameters generation involving hypernetwork pre-training on instruction-following data and generalization fine-tuning on sparse task data. Furthermore, we utilize a constrained training loss and a gradient-based demonstration selection strategy to enhance the training stability and performance. Experimental results and analysis across four benchmark datasets (P3, S-NI, BBH, and SuperGLUE) demonstrate the proposed approach has flexible generalization ability and superior performance.