Shitou Zhang


2024

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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.

2023

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Enhancing Ancient Chinese Understanding with Derived Noisy Syntax Trees
Ping Wang | Shitou Zhang | Zuchao Li | Jingrui Hou
Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 4: Student Research Workshop)

Despite the rapid development of neural-based models, syntax still plays a crucial role in modern natural language processing. However, few studies have incorporated syntactic information into ancient Chinese understanding tasks due to the lack of syntactic annotation. This paper explores the role of syntax in ancient Chinese understanding based on the noisy syntax trees from unsupervised derivation and modern Chinese syntax parsers. On top of that, we propose a novel syntax encoding component – confidence-based syntax encoding network (cSEN) to alleviate the side effects from the existing noise caused by unsupervised syntax derivation and the incompatibility between ancient and modern Chinese. Experiments on two typical ancient Chinese understanding tasks, ancient poetry theme classification and ancient-modern Chinese translation, demonstrate that syntactic information can effectively enhance the understanding of ancient Chinese over strong baselines, and that the proposed cSEN plays an important role in noisy scenarios.