我们提出了Patron,这是一种新方法,它使用基于及时的不确定性估计,用于在冷启动场景下进行预训练的语言模型进行微调的数据选择,即,没有初始标记的数据可用。在顾客中,我们设计(1)一种基于迅速的不确定性传播方法来估计数据点的重要性和(2)分区 - 然后 - 剥离(PTR)策略,以促进对注释的样品多样性。六个文本分类数据集的实验表明,赞助人的表现优于最强的冷启动数据选择基准,高达6.9%。此外,仅具有128个标签,顾客分别基于香草微调和及时的学习,获得了91.0%和92.1%的全面监督性能。我们的赞助人实施可在\ url {https://github.com/yueyu1030/patron}上获得。
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尽管在许多自然语言处理(NLP)任务中进行了预先训练的语言模型(LMS),但它们需要过多标记的数据来进行微调以实现令人满意的性能。为了提高标签效率,研究人员采取了活跃的学习(AL),而大多数事先工作则忽略未标记数据的潜力。要释放未标记数据的强大功能以获得更好的标签效率和模型性能,我们开发ATM,一个新的框架,它利用自我训练来利用未标记的数据,并且对于特定的AL算法不可知,用作改善现有的插件模块Al方法。具体地,具有高不确定性的未标记数据暴露于Oracle以进行注释,而具有低不确定性的人则可用于自培训。为了缓解自我训练中的标签噪声传播问题,我们设计一个简单且有效的基于动量的内存库,可以动态地从所有轮次汇总模型预测。通过广泛的实验,我们证明了ATM优于最强大的积极学习和自我训练基线,平均将标签效率提高51.9%。
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积极的学习有效地收集了无标记的数据以进行注释,从而减少了对标记数据的需求。在这项工作中,我们建议以局部灵敏度和硬度感知的获取功能检索未标记的样品。所提出的方法通过局部扰动生成数据副本,并选择其预测可能性与其副本最大的数据点。我们通过注入选择的情况扰动来进一步增强我们的采集功能。我们的方法可以在各种分类任务中对常用的活跃学习策略获得一致的收益。此外,我们在基于迅速的几次学习中迅速选择的研究中观察到对基准的持续改进。这些实验表明,我们以局部敏感性和硬度为指导的获取对许多NLP任务都是有效和有益的。
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The recent GPT-3 model (Brown et al., 2020) achieves remarkable few-shot performance solely by leveraging a natural-language prompt and a few task demonstrations as input context. Inspired by their findings, we study few-shot learning in a more practical scenario, where we use smaller language models for which fine-tuning is computationally efficient. We present LM-BFF-better few-shot fine-tuning of language models 1 -a suite of simple and complementary techniques for finetuning language models on a small number of annotated examples. Our approach includes (1) prompt-based fine-tuning together with a novel pipeline for automating prompt generation; and (2) a refined strategy for dynamically and selectively incorporating demonstrations into each context. Finally, we present a systematic evaluation for analyzing few-shot performance on a range of NLP tasks, including classification and regression. Our experiments demonstrate that our methods combine to dramatically outperform standard fine-tuning procedures in this low resource setting, achieving up to 30% absolute improvement, and 11% on average across all tasks. Our approach makes minimal assumptions on task resources and domain expertise, and hence constitutes a strong task-agnostic method for few-shot learning. 2 * The first two authors contributed equally. 1 Alternatively, language models' best friends forever. 2 Our implementation is publicly available at https:// github.com/princeton-nlp/LM-BFF.
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How can we extend a pre-trained model to many language understanding tasks, without labeled or additional unlabeled data? Pre-trained language models (PLMs) have been effective for a wide range of NLP tasks. However, existing approaches either require fine-tuning on downstream labeled datasets or manually constructing proper prompts. In this paper, we propose nonparametric prompting PLM (NPPrompt) for fully zero-shot language understanding. Unlike previous methods, NPPrompt uses only pre-trained language models and does not require any labeled data or additional raw corpus for further fine-tuning, nor does it rely on humans to construct a comprehensive set of prompt label words. We evaluate NPPrompt against previous major few-shot and zero-shot learning methods on diverse NLP tasks: including text classification, text entailment, similar text retrieval, and paraphrasing. Experimental results demonstrate that our NPPrompt outperforms the previous best fully zero-shot method by big margins, with absolute gains of 12.8% in accuracy on text classification and 18.9% on the GLUE benchmark.
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迅速的学习方法通​​过诱导更好的几次表现,在他们仍然遵循基于参数的学习范式的同时,引起了自然语言处理的波动。学习中的遗忘和死记硬背的记忆问题可能会遇到不稳定的概括问题。具体而言,香草及时的学习可能难以利用死记硬背的非典型实例,在完全监督的培训或过度贴身模式的情况下使用低射击数据。为了减轻此类局限性,我们以将知识从记忆中解耦的动机发展为有助于模型在概括和记忆之间取得平衡。与香草及时学习相反,重新启动构造了培训实例中的开放式知识店,并在输入,培训和推理过程中实现检索机制,从而使该模型能够从培训语料库中检索相关环境作为能力为提示增强。广泛的实验表明,Retroppt可以在几次射击和零拍设置中获得更好的性能。此外,我们进一步说明,我们提出的撤退可以通过新数据集获得更好的概括能力。对记忆的详细分析确实显示逆转可以减少语言模型对记忆的依赖;因此,改善下游任务的概括。
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大型预训练的语言模型(PLM)的最新进展导致了自然语言理解(NLU)任务的令人印象深刻的增长,并具有特定于任务的微调。但是,直接调整PLM在很大程度上依赖大量的标记实例,这些实例通常很难获得。迅速对PLM的调整已被证明对各种少数次任务很有价值。现有的作品研究基于迅速的NLU任务的基于及时的调整,主要集中于用语言器来得出正确的标签单词或生成及时的模板,以从PLM中启发语义。此外,还对常规数据增强方法进行了验证,可用于少量射击任务。但是,目前几乎没有针对基于及时的调整范式设计的数据增强方法。因此,我们研究了迅速的少数射击学习者的新数据增强问题。由于标签语义对于迅速的调整至关重要,因此我们提出了一种新颖的标签引导数据增强方法促进DA,该方法利用了丰富的标签语义信息以进行数据增强。很少的文本分类任务的广泛实验结果表明,我们提出的框架通过有效利用标签语义和数据扩展来实现自然语言理解来实现卓越的性能。
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Recent studies have revealed the intriguing few-shot learning ability of pretrained language models (PLMs): They can quickly adapt to a new task when fine-tuned on a small amount of labeled data formulated as prompts, without requiring abundant task-specific annotations. Despite their promising performance, most existing few-shot approaches that only learn from the small training set still underperform fully supervised training by nontrivial margins. In this work, we study few-shot learning with PLMs from a different perspective: We first tune an autoregressive PLM on the few-shot samples and then use it as a generator to synthesize a large amount of novel training samples which augment the original training set. To encourage the generator to produce label-discriminative samples, we train it via weighted maximum likelihood where the weight of each token is automatically adjusted based on a discriminative meta-learning objective. A classification PLM can then be fine-tuned on both the few-shot and the synthetic samples with regularization for better generalization and stability. Our approach FewGen achieves an overall better result across seven classification tasks of the GLUE benchmark than existing few-shot learning methods, improving no-augmentation methods by 5+ average points, and outperforming augmentation methods by 3+ average points.
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几乎没有命名的实体识别(NER)对于在有限的资源领域中标记的实体标记至关重要,因此近年来受到了适当的关注。现有的几声方法主要在域内设置下进行评估。相比之下,对于这些固有的忠实模型如何使用一些标记的域内示例在跨域NER中执行的方式知之甚少。本文提出了一种两步以理性为中心的数据增强方法,以提高模型的泛化能力。几个数据集中的结果表明,与先前的最新方法相比,我们的模型无形方法可显着提高跨域NER任务的性能,包括反事实数据增强和及时调用方法。我们的代码可在\ url {https://github.com/lifan-yuan/factmix}上获得。
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提示方法被认为是几次自然语言处理的关键进展之一。最近对基于离散令牌的``硬提示''转移到连续``软提示''的最新研究,这些提示将可学习的向量用作伪提示代币并实现更好的性能。尽管显示出有希望的前景,但观察到这些软宣传的方法在很大程度上依赖良好的初始化来生效。不幸的是,获得软提示的完美初始化需要了解内在语言模型的工作和精心设计,这绝非易事,必须从头开始重新启动每个新任务。为了解决此问题,我们提出了一种称为Metaprompting的广义软提示方法,该方法采用了良好认可的模型 - 静态元学习算法,以自动找到更好的及时初始化,从而快速适应新的促进任务。问题并在四个不同的数据集上带来了显着改善(1次设置的准确性提高了6分),从而实现了新的最新性能。
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Pre-trained language models (PLMs) have exhibited remarkable few-shot learning capabilities when provided a few examples in a natural language prompt as demonstrations of test instances, i.e., in-context learning. However, the performance of in-context learning is susceptible to the choice of prompt format, training examples and the ordering of the training examples. In this paper, we propose a novel nearest-neighbor calibration framework for in-context learning to ease this issue. It is inspired by a phenomenon that the in-context learning paradigm produces incorrect labels when inferring training instances, which provides a useful supervised signal to calibrate predictions. Thus, our method directly augments the predictions with a $k$-nearest-neighbor ($k$NN) classifier over a datastore of cached few-shot instance representations obtained by PLMs and their corresponding labels. Then adaptive neighbor selection and feature regularization modules are introduced to make full use of a few support instances to reduce the $k$NN retrieval noise. Experiments on various few-shot text classification tasks demonstrate that our method significantly improves in-context learning, while even achieving comparable performance with state-of-the-art tuning-based approaches in some sentiment analysis tasks.
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我们研究了用于半监控学习(SSL)的无监督数据选择,其中可以提供大规模的未标记数据集,并且为标签采集预算小额数据子集。现有的SSL方法专注于学习一个有效地集成了来自给定小标记数据和大型未标记数据的信息的模型,而我们专注于选择正确的数据以用于SSL的注释,而无需任何标签或任务信息。直观地,要标记的实例应统称为下游任务的最大多样性和覆盖范围,并且单独具有用于SSL的最大信息传播实用程序。我们以三步数据为中心的SSL方法形式化这些概念,使稳定性和精度的纤维液改善8%的CiFar-10(标记为0.08%)和14%的Imagenet -1k(标记为0.2%)。它也是一种具有各种SSL方法的通用框架,提供一致的性能增益。我们的工作表明,在仔细选择注释数据上花费的小计算带来了大注释效率和模型性能增益,而无需改变学习管道。我们完全无监督的数据选择可以轻松扩展到其他弱监督的学习设置。
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As an important data selection schema, active learning emerges as the essential component when iterating an Artificial Intelligence (AI) model. It becomes even more critical given the dominance of deep neural network based models, which are composed of a large number of parameters and data hungry, in application. Despite its indispensable role for developing AI models, research on active learning is not as intensive as other research directions. In this paper, we present a review of active learning through deep active learning approaches from the following perspectives: 1) technical advancements in active learning, 2) applications of active learning in computer vision, 3) industrial systems leveraging or with potential to leverage active learning for data iteration, 4) current limitations and future research directions. We expect this paper to clarify the significance of active learning in a modern AI model manufacturing process and to bring additional research attention to active learning. By addressing data automation challenges and coping with automated machine learning systems, active learning will facilitate democratization of AI technologies by boosting model production at scale.
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Natural Language Inference (NLI) or Recognizing Textual Entailment (RTE) aims at predicting the relation between a pair of sentences (premise and hypothesis) as entailment, contradiction or semantic independence. Although deep learning models have shown promising performance for NLI in recent years, they rely on large scale expensive human-annotated datasets. Semi-supervised learning (SSL) is a popular technique for reducing the reliance on human annotation by leveraging unlabeled data for training. However, despite its substantial success on single sentence classification tasks where the challenge in making use of unlabeled data is to assign "good enough" pseudo-labels, for NLI tasks, the nature of unlabeled data is more complex: one of the sentences in the pair (usually the hypothesis) along with the class label are missing from the data and require human annotations, which makes SSL for NLI more challenging. In this paper, we propose a novel way to incorporate unlabeled data in SSL for NLI where we use a conditional language model, BART to generate the hypotheses for the unlabeled sentences (used as premises). Our experiments show that our SSL framework successfully exploits unlabeled data and substantially improves the performance of four NLI datasets in low-resource settings. We release our code at: https://github.com/msadat3/SSL_for_NLI.
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One of the most impressive results of recent NLP history is the ability of pre-trained language models to solve new tasks in a zero-shot setting. To achieve this, NLP tasks are framed as natural language prompts, generating a response indicating the predicted output. Nonetheless, the performance in such settings often lags far behind its supervised counterpart, suggesting a large space for potential improvement. In this paper, we explore methods to utilize unlabeled data to improve zero-shot performance. Specifically, we take advantage of the fact that multiple prompts can be used to specify a single task, and propose to regularize prompt consistency, encouraging consistent predictions over this diverse set of prompts. Our method makes it possible to fine-tune the model either with extra unlabeled training data, or directly on test input at inference time in an unsupervised manner. In experiments, our approach outperforms the state-of-the-art zero-shot learner, T0 (Sanh et al., 2022), on 9 out of 11 datasets across 4 NLP tasks by up to 10.6 absolute points in terms of accuracy. The gains are often attained with a small number of unlabeled examples.
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最近,与“预训练,及时和预测”的新范式相比,与“预训练,微调”范式相比,新的范式“预训练,及时和预测”取得了显着的成就。在基于及时的GPT-3成功之后,一系列基于蒙版的语言模型(MLM)(例如Bert,Roberta)及时学习方法变得流行并广泛使用。但是,另一个有效的预训练的判别模型Electra可能被忽略了。在本文中,我们尝试使用拟议的替换代替令牌检测(RTD)基于基于的及时学习方法来完成零摄像的几个NLP任务。实验结果表明,基于RTD-Prompt学习的Electra模型可达到令人惊讶的最先进的零拍性能。在数字上,与MLM-Roberta-Large和MLM-Bert-Large相比,我们的RTD-Electra-Large在所有15个任务上平均提高了约8.4%和13.7%。特别是在SST-2任务上,我们的RTD-Electra-Large在没有任何培训数据的情况下达到了令人惊讶的90.1%精度。总体而言,与预先训练的蒙版语言模型相比,预先训练的代替令牌检测模型在零拍学习中的性能更好。因此,Electra是一位出色的零球学习者。源代码可在以下网址获得:https://github.com/nishiwen1214/rtd-electra。
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We introduce TeSS (Text Similarity Comparison using Sentence Encoder), a framework for zero-shot classification where the assigned label is determined by the embedding similarity between the input text and each candidate label prompt. We leverage representations from sentence encoders optimized to locate semantically similar samples closer to each other in embedding space during pre-training. The label prompt embeddings serve as prototypes of their corresponding class clusters. Furthermore, to compensate for the potentially poorly descriptive labels in their original format, we retrieve semantically similar sentences from external corpora and additionally use them with the original label prompt (TeSS-R). TeSS outperforms strong baselines on various closed-set and open-set classification datasets under zero-shot setting, with further gains when combined with label prompt diversification through retrieval. These results are robustly attained to verbalizer variations, an ancillary benefit of using a bi-encoder. Altogether, our method serves as a reliable baseline for zero-shot classification and a simple interface to assess the quality of sentence encoders.
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Natural language prompts have been shown to facilitate cross-task generalization for large language models. However, with no or limited labeled examples, the cross-task performance is highly sensitive to the choice of prompts, while selecting a high-performing prompt is challenging given the scarcity of labels. To address the issue, we propose a Zero-Label Prompt Selection (ZPS) method that selects prompts without any labeled data or gradient update. Specifically, given the candidate human-written prompts for a task, ZPS labels a set of unlabeled data with a prompt ensemble and uses the pseudo-labels for prompt selection. Experiments show that ZPS improves over prior methods by a sizeable margin in zero-label performance. We also extend ZPS to a few-shot setting and show its advantages over strong baselines such as prompt tuning and model tuning.
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Self-training (ST) has prospered again in language understanding by augmenting the fine-tuning of pre-trained language models when labeled data is insufficient. However, it remains challenging to incorporate ST into attribute-controllable language generation. Augmented by only self-generated pseudo text, generation models over-emphasize exploitation of the previously learned space, suffering from a constrained generalization boundary. We revisit ST and propose a novel method, DuNST to alleviate this problem. DuNST jointly models text generation and classification with a shared Variational AutoEncoder and corrupts the generated pseudo text by two kinds of flexible noise to disturb the space. In this way, our model could construct and utilize both pseudo text from given labels and pseudo labels from available unlabeled text, which are gradually refined during the ST process. We theoretically demonstrate that DuNST can be regarded as enhancing exploration towards the potential real text space, providing a guarantee of improved performance. Experiments on three controllable generation tasks show that DuNST could significantly boost control accuracy while maintaining comparable generation fluency and diversity against several strong baselines.
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半监督学习(SSL)在许多应用领域中已经取得了成功,但这种成功经常涉及任务特定的未标记数据的可用性。知识蒸馏(KD)能够有效地优化紧凑的神经网络,当通过新鲜任务特定的未标记数据蒸馏昂贵的网络时,实现了最佳结果。但是,任务特定的未标记数据可能具有挑战性,特别是对于NLP。我们调查使用生成模型在合成未标记数据中的使用,并呈现一个名为“生成,注释和学习(GAL)”的简单和一般框架。语言模型(LM)用于扫描域中的未标记数据。然后,分类器用于注释这样的数据。最后,综合生成和注释的数据用于推进SSL,KD和NLP和表格任务的几次拍摄学习。为了获得强大的任务特定的LM,我们要么微调来自特定任务的输入的大LM,或者提示具有少数输入示例的大型LM,并且有条件地生成更明显的示例。它还为胶水排行榜上的6层变压器产生了一种新的最先进的。最后,使用GAL的自我训练从UCI存储库的四个表格任务上提供大的收益。
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