在只有有限的数据可用的低资源场景中,自然语言处理(NLP)的建立模型(NLP)具有挑战性。基于优化的元学习算法通过适应良好的模型初始化来处理新任务,从而在低资源场景中实现了有希望的结果。尽管如此,这些方法遭受了记忆过度拟合问题的困扰,在这种情况下,模型倾向于记住元训练任务,而在适应新任务时忽略了支持集。为了解决此问题,我们提出了一种内存模仿元学习(MEMIML)方法,该方法增强了模型对任务适应的支持集的依赖。具体来说,我们引入了一个特定于任务的内存模块来存储支持集信息并构建一个模仿模块,以强制查询集,以模仿存储在存储器中的某些代表性支持集样本的行为。提供了一种理论分析来证明我们方法的有效性,经验结果还表明,我们的方法在文本分类和生成任务上都优于竞争基准。
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几乎没有弹出的文本分类旨在在几个弹奏方案下对文本进行分类。以前的大多数方法都采用基于优化的元学习来获得任务分布。但是,由于少数样本和复杂模型之间的匹配以及有用的任务功能之间的区别,这些方法遭受了过度拟合问题的影响。为了解决这个问题,我们通过梯度相似性(AMGS)方法提出了一种新颖的自适应元学习器,以提高模型的泛化能力。具体而言,拟议的AMG基于两个方面缓解了过度拟合:(i)通过内部循环中的自我监督的辅助任务来获取样品的潜在语义表示并改善模型的概括,(ii)利用适应性元学习者通过适应性元学习者通过梯度通过相似性,可以在外环中基底学习者获得的梯度上增加约束。此外,我们对正则化对整个框架的影响进行系统分析。对几个基准测试的实验结果表明,与最先进的优化元学习方法相比,提出的AMG始终提高了很少的文本分类性能。
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元学习在现有基准测试基准上的成功取决于以下假设:元训练任务的分布涵盖了元测试任务。经常违反任务不足或非常狭窄的元训练任务分布的应用中的假设会导致记忆或学习者过度拟合。最近的解决方案已追求元训练任务的增强,而同时产生正确和充分虚构任务的问题仍然是一个悬而未决的问题。在本文中,我们寻求一种方法,该方法是通过任务上采样网络从任务表示从任务表示的映射任务。此外,最终的方法将对抗性任务上采样(ATU)命名为足以生成可以通过最大化对抗性损失来最大程度地贡献最新元学习者的任务。在几乎没有正弦的回归和图像分类数据集上,我们从经验上验证了ATU在元测试性能中的最新任务增强策略的明显改善以及上采样任务的质量。
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Personalized chatbots focus on endowing the chatbots with a consistent personality to behave like real users and further act as personal assistants. Previous studies have explored generating implicit user profiles from the user's dialogue history for building personalized chatbots. However, these studies only use the response generation loss to train the entire model, thus it is prone to suffer from the problem of data sparsity. Besides, they overemphasize the final generated response's quality while ignoring the correlations and fusions between the user's dialogue history, leading to rough data representations and performance degradation. To tackle these problems, we propose a self-supervised learning framework MCP for capturing better representations from users' dialogue history for personalized chatbots. Specifically, we apply contrastive sampling methods to leverage the supervised signals hidden in user dialog history, and generate the pre-training samples for enhancing the model. We design three pre-training tasks based on three types of contrastive pairs from user dialogue history, namely response pairs, sequence augmentation pairs, and user pairs. We pre-train the utterance encoder and the history encoder towards the contrastive objectives and use these pre-trained encoders for generating user profiles while personalized response generation. Experimental results on two real-world datasets show a significant improvement in our proposed model MCP compared with the existing methods.
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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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模型不合时宜的元学习(MAML)是最成功的元学习技术之一。它使用梯度下降来学习各种任务之间的共同点,从而使模型能够学习其自身参数的元定义,以使用少量标记的培训数据快速适应新任务。几次学习的关键挑战是任务不确定性。尽管可以从具有大量任务的元学习中获得强大的先验,但是由于训练数据集的数量通常太小,因此无法保证新任务的精确模型。在这项研究中,首先,在选择初始化参数的过程中,为特定于任务的学习者提出了新方法,以适应性地学习选择最小化新任务损失的初始化参数。然后,我们建议对元损失部分的两种改进的方法:方法1通过比较元损失差异来生成权重,以提高几个类别时的准确性,而方法2引入了每个任务的同质不确定性,以根据多个损失,以基于多个损失。原始的梯度下降是一种增强新型类别的概括能力的方式,同时确保了准确性的提高。与以前的基于梯度的元学习方法相比,我们的模型在回归任务和少量分类中的性能更好,并提高了模型的鲁棒性,对元测试集中的学习率和查询集。
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Natural Language Generation (NLG) has improved exponentially in recent years thanks to the development of sequence-to-sequence deep learning technologies such as Transformer-based language models. This advancement has led to more fluent and coherent NLG, leading to improved development in downstream tasks such as abstractive summarization, dialogue generation and data-to-text generation. However, it is also apparent that deep learning based generation is prone to hallucinate unintended text, which degrades the system performance and fails to meet user expectations in many real-world scenarios. To address this issue, many studies have been presented in measuring and mitigating hallucinated texts, but these have never been reviewed in a comprehensive manner before. In this survey, we thus provide a broad overview of the research progress and challenges in the hallucination problem in NLG. The survey is organized into two parts: (1) a general overview of metrics, mitigation methods, and future directions; and (2) an overview of task-specific research progress on hallucinations in the following downstream tasks, namely abstractive summarization, dialogue generation, generative question answering, data-to-text generation, machine translation, and visual-language generation. This survey serves to facilitate collaborative efforts among researchers in tackling the challenge of hallucinated texts in NLG.
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大型审慎的语言模型(PLM)通常是通过微调或提示来适应域或任务的。填充需要修改所有参数,并具有足够的数据以避免过度拟合,同时提示不需要培训,也不需要示例,而是限制性能。取而代之的是,我们通过学习学习一般和适应性PLM之间的差异来为数据和参数有效适应。通过我们提出的动态低级别重新聚体和学识渊博的体系结构控制器,通过模型权重和子层结构来表示这种差异。实验对话完成,低资源抽象摘要以及多域语言建模的实验显示了通过域自适应预处理进行适应时间和性能的改善。消融表明我们的任务自适应重新聚体化(TARP)和模型搜索(TAMS)组件分别改进了其他参数效率转移(如适配器和结构学习方法),例如学习的稀疏。
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Interview has been regarded as one of the most crucial step for recruitment. To fully prepare for the interview with the recruiters, job seekers usually practice with mock interviews between each other. However, such a mock interview with peers is generally far away from the real interview experience: the mock interviewers are not guaranteed to be professional and are not likely to behave like a real interviewer. Due to the rapid growth of online recruitment in recent years, recruiters tend to have online interviews, which makes it possible to collect real interview data from real interviewers. In this paper, we propose a novel application named EZInterviewer, which aims to learn from the online interview data and provides mock interview services to the job seekers. The task is challenging in two ways: (1) the interview data are now available but still of low-resource; (2) to generate meaningful and relevant interview dialogs requires thorough understanding of both resumes and job descriptions. To address the low-resource challenge, EZInterviewer is trained on a very small set of interview dialogs. The key idea is to reduce the number of parameters that rely on interview dialogs by disentangling the knowledge selector and dialog generator so that most parameters can be trained with ungrounded dialogs as well as the resume data that are not low-resource. Evaluation results on a real-world job interview dialog dataset indicate that we achieve promising results to generate mock interviews. With the help of EZInterviewer, we hope to make mock interview practice become easier for job seekers.
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控制生成模型以适应具有有限样本的新域是一个艰难的挑战,它正在接受不断的关注。最近,很少拍摄的学习在域适应中显示了有希望的过程。然而,少量学习产生的文本通常没有语言多样性。为了解决这种缺点,我们将文本生成系统的适应框架作为加强学习问题,提供了一种新方法,使文本生成模型容易适应目标域,其域中的数量最小。两个镜头配置中的五个目标域的实验结果表明,当很少有域样品可用时,我们的方法显着优于域适应。
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模型不合时宜的元学习(MAML)可以说是当今最流行的元学习算法之一。然而,它在几次分类上的性能远远远远远远远远远远远远远远落在许多致力于该问题的算法。在本文中,我们指出了如何训练MAML以进行几次分类的几个关键方面。首先,我们发现MAML在其内部循环更新中需要大量的梯度步骤,这与其常见的用法相矛盾。其次,我们发现MAML对元测试过程中的类标签分配敏感。具体而言,MAML Meta-Trains $ n$道分类器的初始化。这些$ n $方式,在元测试期间,然后具有“ $ n!$”的“ $ n!$”排列,并与$ n $新颖的课程配对。我们发现这些排列会导致巨大的准确性差异,从而使MAML不稳定。第三,我们研究了几种使MAML置换不变的方法,其中元训练单个向量以初始化分类头中的所有$ n $重量矢量的初始化。在Miniimagenet和Tieredimagenet等基准数据集上,我们命名Unicorn-MAML的方法在不牺牲MAML的简单性的情况下以与许多最近的几杆分类算法相同甚至优于许多近期的几个次数分类算法。
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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.
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深度学习一直是自然语言处理(NLP)领域的主流技术。但是,这些技术需要许多标记的数据,并且在整个域之间不太概括。元学习是机器学习研究方法的一个领域,以学习更好的学习算法。方法旨在改善各个方面的算法,包括数据效率和概括性。在许多NLP任务中已经显示出方法的功效,但是在NLP中没有系统的调查,这阻碍了更多的研究人员加入该领域。我们使用这篇调查文件的目标是为研究人员提供NLP中相关的元学习作品的指针,并吸引NLP社区的更多关注以推动未来的创新。本文首先介绍了元学习和共同方法的一般概念。然后,我们总结了任务构建设置和用于各种NLP问题的元学习的应用,并审查NLP社区中元学习的发展。
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会话推荐系统(CRS)旨在捕获用户的当前意图,并通过实时多转交流交互提供建议。作为人机互动系统,CRS必须改善用户体验。但是,大多数CRS方法忽略了用户体验的重要性。在本文中,我们为CRS提出了两个关键点,以改善用户体验:(1)像人类一样说话,人类可以根据当前的对话环境以不同的风格说话。 (2)识别精细颗粒的意图,即使对于相同的话语,不同的用户也具有多种良好的意图,这与用户的固有偏好有关。根据观察结果,我们提出了一个新颖的CRS模型,即创建的定制对话推荐系统(CCRS),该系统从三个角度从三个角度定制了用户的CRS模型。对于类似人类的对话服务,我们提出了多式对话响应生成器,该响应响应生成器选择了语音发言的上下文感知语言风格。为了提供个性化的建议,我们在用户固有的偏好的指导下从对话上下文中提取用户当前的细粒度意图。最后,为了自定义每个用户的模型参数,我们从元学习的角度训练模型。广泛的实验和一系列分析表明,我们的CCR在推荐和对话服务上的优势。
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本文对过去二十年来对自然语言生成(NLG)的研究提供了全面的审查,特别是与数据到文本生成和文本到文本生成深度学习方法有关,以及NLG的新应用技术。该调查旨在(a)给出关于NLG核心任务的最新综合,以及该领域采用的建筑;(b)详细介绍各种NLG任务和数据集,并提请注意NLG评估中的挑战,专注于不同的评估方法及其关系;(c)强调一些未来的强调和相对近期的研究问题,因为NLG和其他人工智能领域的协同作用而增加,例如计算机视觉,文本和计算创造力。
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The goal of building dialogue agents that can converse with humans naturally has been a long-standing dream of researchers since the early days of artificial intelligence. The well-known Turing Test proposed to judge the ultimate validity of an artificial intelligence agent on the indistinguishability of its dialogues from humans'. It should come as no surprise that human-level dialogue systems are very challenging to build. But, while early effort on rule-based systems found limited success, the emergence of deep learning enabled great advance on this topic. In this thesis, we focus on methods that address the numerous issues that have been imposing the gap between artificial conversational agents and human-level interlocutors. These methods were proposed and experimented with in ways that were inspired by general state-of-the-art AI methodologies. But they also targeted the characteristics that dialogue systems possess.
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几个射击分类(FSC)需要使用几个(通常为1-5个)数据点的培训模型。事实证明,元学习能够通过培训各种其他分类任务来学习FSC的参数化模型。在这项工作中,我们提出了铂金(使用superodular互信息的半监督模型不可思议的元学习),这是一种新型的半监督模型不合理的元学习框架,使用了子模块化信息(SMI)函数来促进FSC的性能。在元训练期间,使用SMI函数在内部和外循环中利用铂金的数据,并获得元测试的更丰富的元学习参数化。我们在两种情况下研究白金的性能 - 1)未标记的数据点属于与某个插曲的标签集相同的类别集,以及2)在存在不属于的分布类别的地方标记的集合。我们在Miniimagenet,Tieredimagenet和几乎没有Shot-CIFAR100数据集的各种设置上评估了我们的方法。我们的实验表明,铂金优于MAML和半监督的方法,例如用于半监视的FSC的pseduo-Labeling,尤其是对于每个类别的标记示例比例很小。
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如今,基于变压器的模型逐渐成为人工智能先驱的默认选择。即使在几个镜头的情况下,这些模型也会显示出优势。在本文中,我们重新审视了经典方法,并提出了一种新的几次替代方法。具体而言,我们研究了几个镜头的单级问题,该问题实际上以已知样本为参考来检测未知实例是否属于同一类。可以从序列匹配的角度研究此问题。结果表明,使用元学习,经典序列匹配方法,即比较聚集,显着优于变压器。经典方法所需的培训成本要少得多。此外,我们在简单的微调和元学习下进行两种序列匹配方法之间进行了经验比较。元学习导致变压器模型的特征具有高相关尺寸。原因与变压器模型的层和头数密切相关。实验代码和数据可从https://github.com/hmt2014/fewone获得
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这项工作结合了有关预先训练模型编码的对话历史的信息,其含义表示当前系统话语,以实现面向任务对话中的语境语言生成。我们利用预先训练的多上下文转换模型进行从头开始培训的模型中的上下文表示;并利用从预训练的GPT-2调整的模型中的上下文生成的立即使用前面的用户话语。与多种数据集的两个实验表明,通过预先训练的模型编码的上下文信息可提高自动指标和人类评估中的响应生成的性能。我们所呈现的上下文发电机使得更高种类的响应能够更好地适应正在进行的对话。分析上下文大小显示,较长的上下文不会自动导致更好的性能,但是前面的用户话语的直接对上下文生成起着重要作用。此外,我们还提出了一种基于GPT的生成模型的重新排名。实验表明,RE-Ranker选择的响应对自动度量有重大改进。
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Few-shot learning (FSL) is a central problem in meta-learning, where learners must efficiently learn from few labeled examples. Within FSL, feature pre-training has recently become an increasingly popular strategy to significantly improve generalization performance. However, the contribution of pre-training is often overlooked and understudied, with limited theoretical understanding of its impact on meta-learning performance. Further, pre-training requires a consistent set of global labels shared across training tasks, which may be unavailable in practice. In this work, we address the above issues by first showing the connection between pre-training and meta-learning. We discuss why pre-training yields more robust meta-representation and connect the theoretical analysis to existing works and empirical results. Secondly, we introduce Meta Label Learning (MeLa), a novel meta-learning algorithm that learns task relations by inferring global labels across tasks. This allows us to exploit pre-training for FSL even when global labels are unavailable or ill-defined. Lastly, we introduce an augmented pre-training procedure that further improves the learned meta-representation. Empirically, MeLa outperforms existing methods across a diverse range of benchmarks, in particular under a more challenging setting where the number of training tasks is limited and labels are task-specific. We also provide extensive ablation study to highlight its key properties.
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