arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2303.02577cs.CL
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数据增强在有限数据下参数高效微调中的有效性

Effectiveness of Data Augmentation for Parameter Efficient Tuning with Limited Data

Queen’s University(女王大学);National Research Council Canada(加拿大国家研究委员会);University of Ottawa(渥太华大学)

Stephen Obadinma, Hongyu Guo, Xiaodan Zhu

AI总结:

本文研究了在数据稀缺下,EDA、Back Translation 和 Mixup 等数据增强技术对 P-tuning v2 和 LoRA 等参数高效微调方法的影响,发现其效果因技术而异,并指出添加对比损失函数可有效缓解 P-tuning 对增强数据分离能力不足的问题。

摘要:

近期研究表明,在预训练语言模型上使用诸如 prefix tuning(前缀微调,或 P-tuning)等参数高效微调技术,可以在大幅减少可训练参数的同时,取得与 fine-tuning(微调)相当或更优的性能。然而,在数据增强(一种在低数据情境下提升学习效果的常见策略)背景下,此类方法的有效性尚未得到充分探索。本文在数据稀缺条件下,考察了几种流行的任务无关数据增强技术(即 EDA、Back Translation 和 Mixup)在使用两种通用参数高效微调方法(P-tuning v2 和 LoRA)时的有效性。研究表明,数据增强可用于提升 P-tuning 和 LoRA 模型的性能,但每种技术的有效性各异,且某些方法会导致性能显著下降,尤其是在使用较大模型和较难任务时。我们进一步分析了 P-tuning 相比于 fine-tuning 的句子表征,以帮助理解上述行为,并揭示了 P-tuning 通常在将不同类别的增强数据的句子嵌入分离开来方面表现出更有限的能力。此外,它在严重改变的数据上表现更差。然而,我们证明通过添加一个简单的对比损失函数,可以帮助缓解 prefix tuning 的此类问题,从而对增强数据的性能产生大幅提升。

英文摘要:

Recent work has demonstrated that using parameter efficient tuning techniques such as prefix tuning (or P-tuning) on pretrained language models can yield performance that is comparable or superior to fine-tuning while dramatically reducing trainable parameters. Nevertheless, the effectiveness of such methods under the context of data augmentation, a common strategy to improve learning under low data regimes, has not been fully explored. In this paper, we examine the effectiveness of several popular task-agnostic data augmentation techniques, i.e., EDA, Back Translation, and Mixup, when using two general parameter efficient tuning methods, P-tuning v2 and LoRA, under data scarcity. We show that data augmentation can be used to boost the performance of P-tuning and LoRA models, but the effectiveness of each technique varies and certain methods can lead to a notable degradation in performance, particularly when using larger models and on harder tasks. We further analyze the sentence representations of P-tuning compared to fine-tuning to help understand the above behaviour, and reveal how P-tuning generally presents a more limited ability to separate the sentence embeddings from different classes of augmented data. In addition, it displays poorer performance on heavily altered data. However, we demonstrate that by adding a simple contrastive loss function it can help mitigate such issues for prefix tuning, resulting in sizable improvements to augmented data performance.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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