Xiao Tong


2024

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Translate-and-Revise: Boosting Large Language Models for Constrained Translation
Huang Pengcheng | Mu Yongyu | Wu Yuzhang | Li Bei | Xiao Chunyang | Xiao Tong | Jingbo Zhu
Proceedings of the 23rd Chinese National Conference on Computational Linguistics (Volume 1: Main Conference)

“Imposing constraints on machine translation systems presents a challenging issue because thesesystems are not trained to make use of constraints in generating adequate, fluent translations. Inthis paper, we leverage the capabilities of large language models (LLMs) for constrained trans-lation, given that LLMs can easily adapt to this task by taking translation instructions and con-straints as prompts. However, LLMs cannot always guarantee the adequacy of translation, and,in some cases, ignore the given constraints. This is in part because LLMs might be overly confi-dent in their predictions, overriding the influence of the constraints. To overcome this overidingbehaviour, we propose to add a revision process that encourages LLMs to correct the outputs byprompting them about the constraints that have not yet been met. We evaluate our approach onfour constrained translation tasks, encompassing both lexical and structural constraints in mul-tiple constraint domains. Experiments show 15% improvement in constraint-based translationaccuracy over standard LLMs and the approach also significantly outperforms neural machinetranslation (NMT) state-of-the-art methods.IntroductionConstrained translation seeks to generate translations that adhere to pre-specified constraints. Toachieve this, conventional approaches impose constraints on machine translation systems and force themto follow the constraints during inference (Hokamp and Liu, 2017; Hasler et al., 2018; Dinu et al., 2019;Bergmanis and Pinnis, 2021b; Wang et al., 2022b; Ailem et al., 2022). More recently, large languagemodels (LLMs) have been shown to be strong translation systems (Hendy et al., 2023; Moslem et al.,2023). They provide a general way to involve various instructions, demonstrations, and constraints intothe translation process (Mu et al., 2023; Bogoychev and Chen, 2023), enabling us to perform constrainedtranslation using off-the-shelf, well-trained LLMs.”

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Prior Constraints-based Reward Model Training for Aligning Large Language Models
Zhou Hang | Wang Chenglong | Hu Yimin | Xiao Tong | Zhang Chunliang | Zhu Jingbo
Proceedings of the 23rd Chinese National Conference on Computational Linguistics (Volume 1: Main Conference)

“Reinforcement learning with human feedback for aligning large language models (LLMs) trainsa reward model typically using ranking loss with comparison pairs. However, the training pro-cedure suffers from an inherent problem: the uncontrolled scaling of reward scores during rein-forcement learning due to the lack of constraints while training the reward model. This paperproposes a Prior Constraints-based Reward Model (PCRM) training method to mitigate thisproblem. PCRM incorporates prior constraints—specifically, length ratio and cosine similaritybetween outputs of each comparison pair—during reward model training to regulate optimiza-tion magnitude and control score margins. We comprehensively evaluate PCRM by examining itsrank correlation with human preferences and its effectiveness in aligning LLMs via RL. Exper-imental results demonstrate that PCRM significantly improves alignment performance by effec-tively constraining reward score scaling. As another bonus, our method is easily integrated intoarbitrary rank-based alignment methods, such as direct preference optimization, and can yieldconsistent improvement. The code is available at https://github.com/wangclnlp/DeepSpeed-Chat-Extension/tree/PCRM.”

2023

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Overcoming Language Priors with Counterfactual Inference for Visual Question Answering
Ren Zhibo | Wang Huizhen | Zhu Muhua | Wang Yichao | Xiao Tong | Zhu Jingbo
Proceedings of the 22nd Chinese National Conference on Computational Linguistics

“Recent years have seen a lot of efforts in attacking the issue of language priors in the field ofVisual Question Answering (VQA). Among the extensive efforts, causal inference is regarded asa promising direction to mitigate language bias by weakening the direct causal effect of questionson answers. In this paper, we follow the same direction and attack the issue of language priorsby incorporating counterfactual data. Moreover, we propose a two-stage training strategy whichis deemed to make better use of counterfactual data. Experiments on the widely used bench-mark VQA-CP v2 demonstrate the effectiveness of the proposed approach, which improves thebaseline by 21.21% and outperforms most of the previous systems.”