事件参数提取(EAE)的目的是从文本中提取具有给定角色的参数,这些参数已在自然语言处理中得到广泛研究。以前的大多数作品在具有专用神经体系结构的特定EAE数据集中取得了良好的性能。鉴于,这些架构通常很难适应具有各种注释模式或格式的新数据集/方案。此外,他们依靠大规模标记的数据进行培训,由于大多数情况下的标签成本高,因此无法获得培训。在本文中,我们提出了一个具有变异信息瓶颈的多格式转移学习模型,该模型利用了信息,尤其是新数据集中EAE现有数据集中的常识。具体而言,我们引入了一个共享特定的及时框架,以从具有不同格式的数据集中学习格式共享和格式特定的知识。为了进一步吸收EAE的常识并消除无关的噪音,我们将变异信息瓶颈整合到我们的体系结构中以完善共享表示。我们在三个基准数据集上进行了广泛的实验,并在EAE上获得新的最先进的性能。
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隐式事件参数提取(EAE)旨在确定可以散布在文档上的参数。以前的大多数工作都集中在学习参数和给定的触发因素之间的直接关系,而与远程依赖关系的隐式关系并未得到很好的研究。此外,最近基于神经网络的方法取决于大量的标记数据进行培训,这是由于高标签成本而无法获得的。在本文中,我们提出了一种基于课程学习的及时调整(CUP)方法,该方法通过四个学习阶段解决了隐性的EAE。阶段是根据语义图中与触发节点的关系定义的,该阶段很好地捕获了参数和触发器之间的长距离依赖关系。此外,我们将基于及时的编码器模型集成在一起,以从每个阶段中从预训练的语言模型(PLM)中获取相关的知识,在该阶段中,及时模板适应了学习进度以增强参数的推理。两个众所周知的基准数据集的实验结果显示了我们提出的方法的巨大优势。特别是,我们在完全监督和低数据的场景中胜过最先进的模型。
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旨在从非结构化文本中提取结构信息的知识提取(KE)通常会遭受数据稀缺性和新出现的看不见类型,即低资源场景。许多低资源KE的神经方法已广泛研究并取得了令人印象深刻的表现。在本文中,我们在低资源场景中介绍了对KE的文献综述,并将现有作品分为三个范式:(1)利用更高的资源数据,(2)利用更强的模型,(3)利用数据和模型一起。此外,我们描述了有前途的应用,并概述了未来研究的一些潜在方向。我们希望我们的调查能够帮助学术和工业界更好地理解这一领域,激发更多的想法并提高更广泛的应用。
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Frame Semantic Role Labeling (FSRL) identifies arguments and labels them with frame semantic roles defined in FrameNet. Previous researches tend to divide FSRL into argument identification and role classification. Such methods usually model role classification as naive multi-class classification and treat arguments individually, which neglects label semantics and interactions between arguments and thus hindering performance and generalization of models. In this paper, we propose a query-based framework named ArGument Extractor with Definitions in FrameNet (AGED) to mitigate these problems. Definitions of frames and frame elements (FEs) in FrameNet can be used to query arguments in text. Encoding text-definition pairs can guide models in learning label semantics and strengthening argument interactions. Experiments show that AGED outperforms previous state-of-the-art by up to 1.3 F1-score in two FrameNet datasets and the generalization power of AGED in zero-shot and fewshot scenarios. Our code and technical appendix is available at https://github.com/PKUnlp-icler/AGED.
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临床领域中的事件提取是一个探索较少的研究领域。除了大量的特定领域的行话外,缺乏培训数据,包括较长的实体,具有模糊的边界,使该任务尤其具有挑战性。在本文中,我们介绍了DICE,这是一种用于临床事件提取的强大而数据效率的生成模型。骰子框架事件提取作为有条件的生成问题,并利用域专家提供的描述来提高低资源设置下的性能。此外,DICE学会了与辅助提及的识别任务一起定位和约束生物医学提及,该任务与事件提取任务共同培训,以利用任务间的依赖性,并进一步纳入确定的提及作为其各自任务的触发和论证候选者。我们还介绍了MacCrobat-EE,这是第一个带有事件参数注释的临床事件提取数据集。我们的实验证明了在临床领域的低数据设置下骰子的鲁棒性,以及将柔性关节训练并提及标记纳入生成方法的好处。
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大多数NER方法都依赖于广泛的标记数据进行模型培训,这些数据在低资源场景中挣扎,培训数据有限。与资源丰富的源域相比,现有的主要方法通常会遇到目标域具有不同标签集的挑战,该标签集可以作为类传输和域转移得出的结论。在本文中,我们通过可拔出的提示(Lightner)提出了一个轻巧的调整范式,用于低资源。具体而言,我们构建了实体类别的统一可学习的语言器,以生成实体跨度序列和实体类别,而无需任何标签特定的分类器,从而解决了类转移问题。我们通过将可学习的参数纳入自我发言层作为指导,进一步提出了一个可插入的指导模块,该参数可以重新调节注意力并调整预训练的权重。请注意,我们仅通过修复了预训练的语言模型的整个参数来调整那些插入的模块,从而使我们的方法轻巧且灵活地适合低资源场景,并且可以更好地跨域传输知识。实验结果表明,Lightner可以在标准监督环境中获得可比的性能,并且在低资源设置中优于强大基线。代码在https://github.com/zjunlp/deepke/tree/main/main/example/ner/few-shot中。
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从文本中获取结构事件知识的事件提取(EE)可以分为两个子任务:事件类型分类和元素提取(即在不同的角色模式下识别触发器和参数)。由于不同的事件类型始终拥有独特的提取模式(即角色模式),因此EE先前的工作通常遵循孤立的学习范式,对不同的事件类型独立执行元素提取。它忽略了事件类型和参数角色之间有意义的关联,导致频繁类型/角色的性能相对较差。本文提出了一个新型的EE任务神经关联框架。给定文档,它首先通过构造文档级别的图形来执行类型分类,以关联不同类型的句子节点,并采用图形注意网络来学习句子嵌入。然后,通过构建一个通用参数角色模式来实现元素提取,并具有参数遗传机制,以增强提取元素的角色偏好。因此,我们的模型考虑了EE期间的类型和角色关联,从而使它们之间的隐式信息共享。实验结果表明,我们的方法始终优于两个子任务中大多数最新的EE方法。特别是,对于具有较少培训数据的类型/角色,该性能优于现有方法。
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事件提取(EE)是信息提取的重要任务,该任务旨在从非结构化文本中提取结构化事件信息。大多数先前的工作都专注于提取平坦的事件,同时忽略重叠或嵌套的事件。多个重叠和嵌套EE的模型包括几个连续的阶段来提取事件触发器和参数,这些阶段患有错误传播。因此,我们设计了一种简单而有效的标记方案和模型,以将EE作为单词关系识别,称为oneee。触发器或参数单词之间的关系在一个阶段同时识别出并行网格标记,从而产生非常快的事件提取速度。该模型配备了自适应事件融合模块,以生成事件感知表示表示和距离感知的预测指标,以整合单词关系识别的相对距离信息,从经验上证明这是有效的机制。对3个重叠和嵌套的EE基准测试的实验,即少数FC,GENIA11和GENIA13,表明Oneee实现了最新的(SOTA)结果。此外,ONEEE的推理速度比相同条件下的基线的推理速度快,并且由于它支持平行推断,因此可以进一步改善。
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从新闻文章中提取事件的信息论点是信息提取的一个具有挑战性的问题,这需要对每个文档的全球上下文理解。尽管有关文档级提取的最新工作已经超越了单句子,并提高了端到端模型的跨句子推理能力,但它们仍然受到某些输入序列长度约束的限制,通常忽略事件之间的全局上下文。为了解决此问题,我们通过构建文档存储器存储来记录上下文事件信息,并利用它隐含,明确地帮助解码以后事件的参数,从而引入了一个新的基于全局神经生成的框架,以用于文档级事件参数提取提取文档级别的事件参数提取。经验结果表明,我们的框架的表现要优于先验方法,并且使用约束的解码设计对对抗注释的示例更为强大。 (我们的代码和资源可在https://github.com/xinyadu/memory_docie上获得研究目的。)
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我们提出了一个新的框架,在增强的自然语言(TANL)之间的翻译,解决了许多结构化预测语言任务,包括联合实体和关系提取,嵌套命名实体识别,关系分类,语义角色标记,事件提取,COREREFED分辨率和对话状态追踪。通过培训特定于特定于任务的鉴别分类器来说,我们将其作为一种在增强的自然语言之间的翻译任务,而不是通过培训问题,而不是解决问题,而是可以轻松提取任务相关信息。我们的方法可以匹配或优于所有任务的特定于任务特定模型,特别是在联合实体和关系提取(Conll04,Ade,NYT和ACE2005数据集)上实现了新的最先进的结果,与关系分类(偶尔和默示)和语义角色标签(Conll-2005和Conll-2012)。我们在使用相同的架构和超参数的同时为所有任务使用相同的架构和超级参数,甚至在培训单个模型时同时解决所有任务(多任务学习)。最后,我们表明,由于更好地利用标签语义,我们的框架也可以显着提高低资源制度的性能。
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We propose P4E, an identify-and-localize event detection framework that integrates the best of few-shot prompting and structured prediction. Our framework decomposes event detection into an identification task and a localization task. For the identification task, which we formulate as multi-label classification, we leverage cloze-based prompting to align our objective with the pre-training task of language models, allowing our model to quickly adapt to new event types. We then employ an event type-agnostic sequence labeling model to localize the event trigger conditioned on the identification output. This heterogeneous model design allows P4E to quickly learn new event types without sacrificing the ability to make structured predictions. Our experiments demonstrate the effectiveness of our proposed design, and P4E shows superior performance for few-shot event detection on benchmark datasets FewEvent and MAVEN and comparable performance to SOTA for fully-supervised event detection on ACE.
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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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Pre-trained Language Models (PLMs) have been applied in NLP tasks and achieve promising results. Nevertheless, the fine-tuning procedure needs labeled data of the target domain, making it difficult to learn in low-resource and non-trivial labeled scenarios. To address these challenges, we propose Prompt-based Text Entailment (PTE) for low-resource named entity recognition, which better leverages knowledge in the PLMs. We first reformulate named entity recognition as the text entailment task. The original sentence with entity type-specific prompts is fed into PLMs to get entailment scores for each candidate. The entity type with the top score is then selected as final label. Then, we inject tagging labels into prompts and treat words as basic units instead of n-gram spans to reduce time complexity in generating candidates by n-grams enumeration. Experimental results demonstrate that the proposed method PTE achieves competitive performance on the CoNLL03 dataset, and better than fine-tuned counterparts on the MIT Movie and Few-NERD dataset in low-resource settings.
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跨度提取,旨在从纯文本中提取文本跨度(如单词或短语),是信息提取中的基本过程。最近的作品介绍了通过将跨度提取任务正式化为问题(QA正式化)的跨度提取任务来提高文本表示,以实现最先进的表现。然而,QA正规化并没有充分利用标签知识并遭受培训/推理的低效率。为了解决这些问题,我们介绍了一种新的范例来整合标签知识,并进一步提出一个小说模型,明确有效地将标签知识集成到文本表示中。具体而言,它独立地编码文本和标签注释,然后将标签知识集成到文本表示中,并使用精心设计的语义融合模块进行文本表示。我们在三个典型的跨度提取任务中进行广泛的实验:扁平的网,嵌套网和事件检测。实证结果表明,我们的方法在四个基准测试中实现了最先进的性能,而且分别将培训时间和推理时间降低76%和77%,与QA形式化范例相比。我们的代码和数据可在https://github.com/apkepers/lear中获得。
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Event Extraction (EE) is one of the fundamental tasks in Information Extraction (IE) that aims to recognize event mentions and their arguments (i.e., participants) from text. Due to its importance, extensive methods and resources have been developed for Event Extraction. However, one limitation of current research for EE involves the under-exploration for non-English languages in which the lack of high-quality multilingual EE datasets for model training and evaluation has been the main hindrance. To address this limitation, we propose a novel Multilingual Event Extraction dataset (MEE) that provides annotation for more than 50K event mentions in 8 typologically different languages. MEE comprehensively annotates data for entity mentions, event triggers and event arguments. We conduct extensive experiments on the proposed dataset to reveal challenges and opportunities for multilingual EE.
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The spread of rumors along with breaking events seriously hinders the truth in the era of social media. Previous studies reveal that due to the lack of annotated resources, rumors presented in minority languages are hard to be detected. Furthermore, the unforeseen breaking events not involved in yesterday's news exacerbate the scarcity of data resources. In this work, we propose a novel zero-shot framework based on prompt learning to detect rumors falling in different domains or presented in different languages. More specifically, we firstly represent rumor circulated on social media as diverse propagation threads, then design a hierarchical prompt encoding mechanism to learn language-agnostic contextual representations for both prompts and rumor data. To further enhance domain adaptation, we model the domain-invariant structural features from the propagation threads, to incorporate structural position representations of influential community response. In addition, a new virtual response augmentation method is used to improve model training. Extensive experiments conducted on three real-world datasets demonstrate that our proposed model achieves much better performance than state-of-the-art methods and exhibits a superior capacity for detecting rumors at early stages.
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在文档级事件提取(DEE)任务中,事件参数始终散布在句子(串行问题)中,并且多个事件可能存在于一个文档(多事件问题)中。在本文中,我们认为事件参数的关系信息对于解决上述两个问题具有重要意义,并提出了一个新的DEE框架,该框架可以对关系依赖关系进行建模,称为关系授权的文档级事件提取(REDEE)。更具体地说,该框架具有一种新颖的量身定制的变压器,称为关系增强的注意变形金刚(RAAT)。 RAAT可扩展以捕获多尺度和多启动参数关系。为了进一步利用关系信息,我们介绍了一个单独的事件关系预测任务,并采用多任务学习方法来显式增强事件提取性能。广泛的实验证明了该方法的有效性,该方法可以在两个公共数据集上实现最新性能。我们的代码可在https:// github上找到。 com/tencentyouturesearch/raat。
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语义角色标签(SRL)旨在识别句子的谓词题目结构,并可以分解为两个子任务:谓词歧义歧义和参数标记。先前的工作独立处理这两个任务,这两个任务忽略了两个任务之间的语义连接。在本文中,我们建议使用机器阅读理解(MRC)框架来弥合这一差距。我们将谓词歧义形式化为多项选择的机器阅读理解,其中给定谓词的候选感官的描述用作选择正确的感觉的选项。然后使用所选的谓词感来确定该谓词的语义角色,这些语义角色用于构建另一个MRC模型的查询以进行参数标记。这样,我们能够利用参数标记的谓词语义和语义角色语义。我们还建议为计算效率选择所有可能的语义角色的子集。实验表明,所提出的框架可实现与先前工作的最新结果或可比的结果。代码可在\ url {https://github.com/shannonai/mrc-srl}上获得。
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Translating training data into many languages has emerged as a practical solution for improving cross-lingual transfer. For tasks that involve span-level annotations, such as information extraction or question answering, an additional label projection step is required to map annotated spans onto the translated texts. Recently, a few efforts have utilized a simple mark-then-translate method to jointly perform translation and projection by inserting special markers around the labeled spans in the original sentence. However, as far as we are aware, no empirical analysis has been conducted on how this approach compares to traditional annotation projection based on word alignment. In this paper, we present an extensive empirical study across 42 languages and three tasks (QA, NER, and Event Extraction) to evaluate the effectiveness and limitations of both methods, filling an important gap in the literature. Experimental results show that our optimized version of mark-then-translate, which we call EasyProject, is easily applied to many languages and works surprisingly well, outperforming the more complex word alignment-based methods. We analyze several key factors that affect end-task performance, and show EasyProject works well because it can accurately preserve label span boundaries after translation. We will publicly release all our code and data.
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Query-focused summarization has been considered as an important extension for text summarization. It aims to generate a concise highlight for a given query. Different from text summarization, query-focused summarization has long been plagued by the problem of lacking high-quality large-scale datasets. In this paper, we investigate the idea that whether we can integrate and transfer the knowledge of text summarization and question answering to assist the few-shot learning in query-focused summarization. Here, we propose prefix-merging, a prefix-based pretraining strategy for few-shot learning in query-focused summarization. Drawn inspiration from prefix-tuning, we are allowed to integrate the task knowledge from text summarization and question answering into a properly designed prefix and apply the merged prefix to query-focused summarization. With only a small amount of trainable parameters, prefix-merging outperforms fine-tuning on query-focused summarization. We further discuss the influence of different prefix designs and propose a visualized explanation for how prefix-merging works.
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