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.

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.

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。

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。

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。

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.

GPT-3等大型语言模型是优秀的几次学习者，允许他们通过自然文本提示来控制。最近的研究报告称，基于及时的直接分类消除了对微调的需求，但缺乏数据和推理可扩展性。本文提出了一种新的数据增强技术，利用大规模语言模型来生成来自真实样本的混合的现实文本样本。我们还建议利用语言模型预测的软标签，从大规模语言模型中有效地蒸馏知识并同时创建文本扰动。我们对各种分类任务进行数据增强实验，并显示我们的方法非常优于现有的文本增强方法。消融研究和定性分析为我们的方法提供了更多的见解。

我们研究了很少的细粒实体键入（FET）的问题，其中只有几个带注释的实体对每种实体类型提供了上下文。最近，基于及时的调整通过将实体类型分类任务作为“填补空白”的问题来表明在几次射击方案中表现出优越的性能。这允许有效利用预训练的语言模型（PLM）的强语建模能力。尽管当前基于及时的调整方法成功了，但仍有两个主要挑战：（1）提示中的口头化器要么是由外部知识基础手动设计或构建的，而无需考虑目标语料库和标签层次结构信息，而且（2）当前方法主要利用PLM的表示能力，但没有通过广泛的通用域预训练来探索其产生的功率。在这项工作中，我们为由两个模块组成的几个弹药fet提出了一个新颖的框架：（1）实体类型标签解释模块自动学习将类型标签与词汇联系起来，通过共同利用几个播放实例和标签层次结构和标签层次结构，以及（2）基于类型的上下文化实例生成器根据给定实例生成新实例，以扩大培训集以更好地概括。在三个基准数据集上，我们的模型优于大量利润的现有方法。可以在https://github.com/teapot123/fine-graining-entity-typing上找到代码。

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.

及时调整是将预训练模型调整到下游任务的极其有效的工具。但是，基于标准及时的方法主要考虑下游任务的足够数据的情况。目前尚不清楚是否可以将优势传输到几杆式制度，在每个下游任务中只有有限的数据。尽管有些作品证明了在几次弹奏设置下及时调整的潜力，但通过搜索离散提示或使用有限数据调整软提示的主流方法仍然非常具有挑战性。通过广泛的实证研究，我们发现迅速调整和完全微调之间的学习差距仍然存在差距。为了弥合差距，我们提出了一个新的及时调整框架，称为软模板调整（STT）。 STT结合了手册和自动提示，并将下游分类任务视为掩盖语言建模任务。对不同设置的全面评估表明，STT可以在不引入其他参数的情况下缩小微调和基于及时的方法之间的差距。值得注意的是，它甚至可以胜过情感分类任务的时间和资源消耗的微调方法。

最近的几种方法，例如参数有效的微调（PEFT）和模式开发训练（PET），在标签筛选设置中取得了令人印象深刻的结果。但是，它们很难使用，因为它们会受到手动制作的提示的高度可变性，并且通常需要十亿参数语言模型才能达到高精度。为了解决这些缺点，我们提出了SETFIT（句子变压器微调），这是一个有效且迅速的框架，用于对句子变形金刚（ST）进行几次微调。 SetFit首先以对比的暹罗方式对少数文本对进行微调验证的st。然后将所得模型用于生成丰富的文本嵌入，这些嵌入方式用于训练分类头。这个简单的框架不需要任何提示或口头化，并且比现有技术少的参数较少，因此可以实现高精度。我们的实验表明，SetFit通过PEFT和PET技术获得了可比的结果，同时训练的速度更快。我们还表明，SETFIT可以通过简单地切换ST主体来应用于多语言设置。我们的代码可从https://github.com/huggingface/setFit以及我们的数据集获得，网址为https://huggingface.co/setfit。

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.

Prompt learning recently become an effective linguistic tool to motivate the PLMs' knowledge on few-shot-setting tasks. However, studies have shown the lack of robustness still exists in prompt learning, since suitable initialization of continuous prompt and expert-first manual prompt are essential in fine-tuning process. What is more, human also utilize their comparative ability to motivate their existing knowledge for distinguishing different examples. Motivated by this, we explore how to use contrastive samples to strengthen prompt learning. In detail, we first propose our model ConsPrompt combining with prompt encoding network, contrastive sampling module, and contrastive scoring module. Subsequently, two sampling strategies, similarity-based and label-based strategies, are introduced to realize differential contrastive learning. The effectiveness of proposed ConsPrompt is demonstrated in five different few-shot learning tasks and shown the similarity-based sampling strategy is more effective than label-based in combining contrastive learning. Our results also exhibits the state-of-the-art performance and robustness in different few-shot settings, which proves that the ConsPrompt could be assumed as a better knowledge probe to motivate PLMs.

Through in-context learning (ICL), large-scale language models are effective few-shot learners without additional model fine-tuning. However, the ICL performance does not scale well with the number of available training samples as it is limited by the inherent input length constraint of the underlying language model. Meanwhile, many studies have revealed that language models are also powerful feature extractors, allowing them to be utilized in a black-box manner and enabling the linear probing paradigm, where lightweight discriminators are trained on top of the pre-extracted input representations. This paper proposes prompt-augmented linear probing (PALP), a hybrid of linear probing and ICL, which leverages the best of both worlds. PALP inherits the scalability of linear probing and the capability of enforcing language models to derive more meaningful representations via tailoring input into a more conceivable form. Throughout in-depth investigations on various datasets, we verified that PALP significantly enhances the input representations closing the gap between ICL in the data-hungry scenario and fine-tuning in the data-abundant scenario with little training overhead, potentially making PALP a strong alternative in a black-box scenario.

Controllable Text Generation (CTG) is emerging area in the field of natural language generation (NLG). It is regarded as crucial for the development of advanced text generation technologies that are more natural and better meet the specific constraints in practical applications. In recent years, methods using large-scale pre-trained language models (PLMs), in particular the widely used transformer-based PLMs, have become a new paradigm of NLG, allowing generation of more diverse and fluent text. However, due to the lower level of interpretability of deep neural networks, the controllability of these methods need to be guaranteed. To this end, controllable text generation using transformer-based PLMs has become a rapidly growing yet challenging new research hotspot. A diverse range of approaches have emerged in the recent 3-4 years, targeting different CTG tasks which may require different types of controlled constraints. In this paper, we present a systematic critical review on the common tasks, main approaches and evaluation methods in this area. Finally, we discuss the challenges that the field is facing, and put forward various promising future directions. To the best of our knowledge, this is the first survey paper to summarize CTG techniques from the perspective of PLMs. We hope it can help researchers in related fields to quickly track the academic frontier, providing them with a landscape of the area and a roadmap for future research.

最近的自然语言理解进展（NLU）已经被驱动，部分是由胶水，超级格，小队等的基准。事实上，许多NLU模型现在在许多任务中匹配或超过“人类水平”性能这些基准。然而，大多数这些基准测试都提供模型访问相对大量的标记数据进行培训。因此，该模型提供了比人类所需的更多数据，以实现强大的性能。这有动机侧重于侧重于改善NLU模型的少量学习性能。然而，缺乏少量射门的标准化评估基准，导致不同纸张中的不同实验设置。为了帮助加速这一工作的工作，我们介绍了线索（受限制的语言理解评估标准），这是评估NLU模型的几次拍摄学习功能的基准。我们证明，虽然最近的模型在获得大量标记数据时达到人类性能，但对于大多数任务，少量拍摄设置中的性能存在巨大差距。我们还展示了几个拍摄设置中替代模型家族和适应技术之间的差异。最后，我们讨论了在设计实验设置时讨论了评估真实少量学习绩效的实验设置，并提出了统一的标准化方法，以获得少量学习评估。我们的目标是鼓励对NLU模型的研究，可以概括为具有少数示例的新任务。线索的代码和数据可以在https://github.com/microsoft/clues提供。

大规模的预训练的语言模型（PLM）以能够仅通过在提示中调节一些被称为示范的示威演示的情况而不明确调整为所需的下游任务而被称为示威的示威来解决任务。但是，这种过程（即，在文章中的学习）自然会高度依赖通常从外部数据集中选择的演示。在本文中，我们提出了自我生成的文化学习（SG-ICL），该学习生成了从PLM本身中的文化学习演示，以最大程度地减少对外部演示的依赖。我们对四个不同的文本分类任务进行实验，并显示SG-ICL的表现明显优于零射击学习，并且通常价值约0.6个黄金训练样本。此外，与培训数据集的随机选择相比，我们的生成的演示表现出更一致的性能，方差较低。

We describe PromptBoosting, a query-efficient procedure for building a text classifier from a neural language model (LM) without access to the LM's parameters, gradients, or hidden representations. This form of "black-box" classifier training has become increasingly important as the cost of training and inference in large-scale LMs grows. But existing black-box LM classifier learning approaches are themselves computationally inefficient, typically specializing LMs to the target task by searching in a large space of (discrete or continuous) prompts using zeroth-order optimization methods. Instead of directly optimizing in prompt space, PromptBoosting obtains a small pool of prompts via a gradient-free approach and then constructs a large pool of weak learners by pairing these prompts with different elements of the LM's output distribution. These weak learners are then ensembled using the AdaBoost algorithm. The entire learning process requires only a small number of forward passes and no backward pass. Experiments show that PromptBoosting achieves state-of-the-art performance in multiple black-box few-shot classification tasks, and matches or outperforms full fine-tuning in both few-shot and standard learning paradigms, while training 10x faster than existing black-box methods.

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.

本文着重于几次NLP任务的文本数据增强。现有的数据增强算法要么使用一个小型培训集来生成新的合成数据，要么利用与任务无关的启发式规则（例如，同义词替代）或微调通用预训练的语言模型（例如GPT2）。因此，这些方法具有特定于任务的知识，并且仅限于在简单任务中为弱基线产生低质量的合成数据。为了解决这个问题，我们提出了知识混合数据增强模型（KNOWDA）：使用知识混合培训（KOMT）在不同的NLP任务的混合物上预测的编码器LM。 KOMT是一种培训程序，将各种异质NLP任务的输入示例重新定义为统一的文本到文本格式，并采用不同粒度的目标，以学习生成部分或完整的样本。在KOMT的帮助下，Knowda可以隐含地将所需的特定于任务的知识从任务的混合中隐含地结合在一起，并通过一些给定的实例迅速掌握目标任务的固有综合定律。据我们所知，我们是首次尝试将任务数量扩展到多任务共同培训以进行数据扩展。广泛的实验表明，i）Knowda成功地通过少量基准的基准成功地提高了Albert和Deberta的表现，表现优于先前的最新数据增强基线； ii）KNOWDA还可以改善少数弹药任务的模型性能，这是KOMT中未包含的固定任务类型。