为了减少人际关系提取(RE)任务的注释,提出了遥远的监督方法,同时却在低性能方面挣扎。在这项工作中,我们提出了一个新颖的DSRE-NLI框架,该框架既考虑了现有知识库的遥远监督,又考虑了对其他任务的预读语言模型的间接监督。 DSRE-NLI通过半自动关系语言(SARV)机制为现成的自然语言推理(NLI)发动机充满电,以提供间接的监督并进一步巩固远处注释以使多型分类重新模型受益。基于NLI的间接监督仅获取一个从人类的关系模板作为每个关系的语义通用模板,然后模板集由高质量的文本模式富集,从遥远的注释的语料库中自动开采。通过两种简单有效的数据整合策略,培训数据的质量得到了显着提高。广泛的实验表明,所提出的框架可显着改善远距离监督的RE基准数据集上的SOTA性能(最高为F1的7.73%)。
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Triplet extraction aims to extract entities and their corresponding relations in unstructured text. Most existing methods train an extraction model on high-quality training data, and hence are incapable of extracting relations that were not observed during training. Generalizing the model to unseen relations typically requires fine-tuning on synthetic training data which is often noisy and unreliable. In this paper, we argue that reducing triplet extraction to a template filling task over a pre-trained language model can equip the model with zero-shot learning capabilities and enable it to leverage the implicit knowledge in the language model. Embodying these ideas, we propose a novel framework, ZETT (ZEro-shot Triplet extraction by Template infilling), that is based on end-to-end generative transformers. Our experiments show that without any data augmentation or pipeline systems, ZETT can outperform previous state-of-the-art models with 25% less parameters. We further show that ZETT is more robust in detecting entities and can be incorporated with automatically generated templates for relations.
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To effectively train accurate Relation Extraction models, sufficient and properly labeled data is required. Adequately labeled data is difficult to obtain and annotating such data is a tricky undertaking. Previous works have shown that either accuracy has to be sacrificed or the task is extremely time-consuming, if done accurately. We are proposing an approach in order to produce high-quality datasets for the task of Relation Extraction quickly. Neural models, trained to do Relation Extraction on the created datasets, achieve very good results and generalize well to other datasets. In our study, we were able to annotate 10,022 sentences for 19 relations in a reasonable amount of time, and trained a commonly used baseline model for each relation.
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关系提取(RE)是自然语言处理的基本任务。RE试图通过识别文本中的实体对之间的关系信息来将原始的,非结构化的文本转变为结构化知识。RE有许多用途,例如知识图完成,文本摘要,提问和搜索查询。RE方法的历史可以分为四个阶段:基于模式的RE,基于统计的RE,基于神经的RE和大型语言模型的RE。这项调查始于对RE的早期阶段的一些示例性作品的概述,突出了局限性和缺点,以使进度相关。接下来,我们回顾流行的基准测试,并严格检查用于评估RE性能的指标。然后,我们讨论遥远的监督,这是塑造现代RE方法发展的范式。最后,我们回顾了重点是降级和培训方法的最新工作。
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Two key obstacles in biomedical relation extraction (RE) are the scarcity of annotations and the prevalence of instances without explicitly pre-defined labels due to low annotation coverage. Existing approaches, which treat biomedical RE as a multi-class classification task, often result in poor generalization in low-resource settings and do not have the ability to make selective prediction on unknown cases but give a guess from seen relations, hindering the applicability of those approaches. We present NBR, which converts biomedical RE as natural language inference formulation through indirect supervision. By converting relations to natural language hypotheses, NBR is capable of exploiting semantic cues to alleviate annotation scarcity. By incorporating a ranking-based loss that implicitly calibrates abstinent instances, NBR learns a clearer decision boundary and is instructed to abstain on uncertain instances. Extensive experiments on three widely-used biomedical RE benchmarks, namely ChemProt, DDI and GAD, verify the effectiveness of NBR in both full-set and low-resource regimes. Our analysis demonstrates that indirect supervision benefits biomedical RE even when a domain gap exists, and combining NLI knowledge with biomedical knowledge leads to the best performance gains.
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Relation extraction (RE) is a sub-discipline of information extraction (IE) which focuses on the prediction of a relational predicate from a natural-language input unit (such as a sentence, a clause, or even a short paragraph consisting of multiple sentences and/or clauses). Together with named-entity recognition (NER) and disambiguation (NED), RE forms the basis for many advanced IE tasks such as knowledge-base (KB) population and verification. In this work, we explore how recent approaches for open information extraction (OpenIE) may help to improve the task of RE by encoding structured information about the sentences' principal units, such as subjects, objects, verbal phrases, and adverbials, into various forms of vectorized (and hence unstructured) representations of the sentences. Our main conjecture is that the decomposition of long and possibly convoluted sentences into multiple smaller clauses via OpenIE even helps to fine-tune context-sensitive language models such as BERT (and its plethora of variants) for RE. Our experiments over two annotated corpora, KnowledgeNet and FewRel, demonstrate the improved accuracy of our enriched models compared to existing RE approaches. Our best results reach 92% and 71% of F1 score for KnowledgeNet and FewRel, respectively, proving the effectiveness of our approach on competitive benchmarks.
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认识到没有培训实例的看不见的关系是现实世界中的一个具有挑战性的任务。在本文中,我们提出了一种基于提示的模型,具有语义知识增强(ZS-SKA),以识别零拍摄设置下的看不见的关系。在新的单词级别句子翻译规则之后,我们从带有所看到的关系的情况生成增强的实例。我们根据外部知识图设计提示,以将从所见关系中学到的语义知识信息集成。我们在提示模板中使用实际标签集,而是构造加权虚拟标签单词。通过生成与增强实例的看见和看不见的关系的表示,并通过原型网络提示,计算距离以预测看不见的关系。在三个公共数据集上进行的广泛实验表明,ZS-SKA优于零击方案下的最先进的方法。我们的实验结果还证明了ZS-SKA的有效性和鲁棒性。
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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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Event extraction (EE) is the task of identifying interested event mentions from text. Conventional efforts mainly focus on the supervised setting. However, these supervised models cannot generalize to event types out of the pre-defined ontology. To fill this gap, many efforts have been devoted to the zero-shot EE problem. This paper follows the trend of modeling event-type semantics but moves one step further. We argue that using the static embedding of the event type name might not be enough because a single word could be ambiguous, and we need a sentence to define the type semantics accurately. To model the definition semantics, we use two separate transformer models to project the contextualized event mentions and corresponding definitions into the same embedding space and then minimize their embedding distance via contrastive learning. On top of that, we also propose a warming phase to help the model learn the minor difference between similar definitions. We name our approach Zero-shot Event extraction with Definition (ZED). Experiments on the MAVEN dataset show that our model significantly outperforms all previous zero-shot EE methods with fast inference speed due to the disjoint design. Further experiments also show that ZED can be easily applied to the few-shot setting when the annotation is available and consistently outperforms baseline supervised methods.
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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。
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我们提出了一种可解释的关系提取方法,通过共同训练这两个目标来减轻概括和解释性之间的张力。我们的方法使用多任务学习体系结构,该体系结构共同训练分类器以进行关系提取,并在解释关系分类器的决策的关系中标记单词的序列模型。我们还将模型输出转换为规则,以将全局解释带入这种方法。使用混合策略对此序列模型进行训练:有监督,当可获得预先存在的模式的监督时,另外还要半监督。在后一种情况下,我们将序列模型的标签视为潜在变量,并学习最大化关系分类器性能的最佳分配。我们评估了两个数据集中的提议方法,并表明序列模型提供了标签,可作为关系分类器决策的准确解释,并且重要的是,联合培训通常可以改善关系分类器的性能。我们还评估了生成的规则的性能,并表明新规则是手动规则的重要附加功能,并使基于规则的系统更接近神经模型。
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Modern supervised learning neural network models require a large amount of manually labeled data, which makes the construction of domain-specific knowledge graphs time-consuming and labor-intensive. In parallel, although there has been much research on named entity recognition and relation extraction based on distantly supervised learning, constructing a domain-specific knowledge graph from large collections of textual data without manual annotations is still an urgent problem to be solved. In response, we propose an integrated framework for adapting and re-learning knowledge graphs from one coarse domain (biomedical) to a finer-define domain (oncology). In this framework, we apply distant-supervision on cross-domain knowledge graph adaptation. Consequently, no manual data annotation is required to train the model. We introduce a novel iterative training strategy to facilitate the discovery of domain-specific named entities and triples. Experimental results indicate that the proposed framework can perform domain adaptation and construction of knowledge graph efficiently.
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命名实体识别(ner)是从文本中提取特定类型的命名实体的任务。当前的NER模型往往依赖于人类注释的数据集,要求在目标领域和实体上广泛参与专业知识。这项工作介绍了一个询问生成的方法,它通过询问反映实体类型的需求的简单自然语言问题来自动生成NER数据集(例如,哪种疾病?)到开放式域问题应答系统。不使用任何域中资源(即,培训句子,标签或域名词典),我们的模型在我们生成的数据集上仅培训了,这在很大程度上超过了四个不同域的六个基准测试的弱势监督模型。令人惊讶的是,在NCBI疾病中,我们的模型达到75.5 F1得分,甚至优于以前的最佳弱监督模型4.1 F1得分,它利用域专家提供的丰富的域名词典。制定具有自然语言的NER的需求,也允许我们为诸如奖项等细粒度实体类型构建NER模型,其中我们的模型甚至优于完全监督模型。在三个少量的NER基准测试中,我们的模型实现了新的最先进的性能。
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作为人类认知的重要组成部分,造成效果关系频繁出现在文本中,从文本策划原因关系有助于建立预测任务的因果网络。现有的因果关系提取技术包括基于知识的,统计机器学习(ML)和基于深度学习的方法。每种方法都具有其优点和缺点。例如,基于知识的方法是可以理解的,但需要广泛的手动域知识并具有较差的跨域适用性。由于自然语言处理(NLP)工具包,统计机器学习方法更加自动化。但是,功能工程是劳动密集型的,工具包可能导致错误传播。在过去的几年里,由于其强大的代表学习能力和计算资源的快速增加,深入学习技术吸引了NLP研究人员的大量关注。它们的局限包括高计算成本和缺乏足够的注释培训数据。在本文中,我们对因果关系提取进行了综合调查。我们最初介绍了因果关系提取中存在的主要形式:显式的内部管制因果关系,隐含因果关系和间情态因果关系。接下来,我们列出了代理关系提取的基准数据集和建模评估方法。然后,我们介绍了三种技术的结构化概述了与他们的代表系统。最后,我们突出了潜在的方向存在现有的开放挑战。
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学术研究是解决以前从未解决过的问题的探索活动。通过这种性质,每个学术研究工作都需要进行文献审查,以区分其Novelties尚未通过事先作品解决。在自然语言处理中,该文献综述通常在“相关工作”部分下进行。鉴于研究文件的其余部分和引用的论文列表,自动相关工作生成的任务旨在自动生成“相关工作”部分。虽然这项任务是在10年前提出的,但直到最近,它被认为是作为科学多文件摘要问题的变种。然而,即使在今天,尚未标准化了自动相关工作和引用文本生成的问题。在这项调查中,我们进行了一个元研究,从问题制定,数据集收集,方法方法,绩效评估和未来前景的角度来比较相关工作的现有文献,以便为读者洞察到国家的进步 - 最内容的研究,以及如何进行未来的研究。我们还调查了我们建议未来工作要考虑整合的相关研究领域。
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Practices in the built environment have become more digitalized with the rapid development of modern design and construction technologies. However, the requirement of practitioners or scholars to gather complicated professional knowledge in the built environment has not been satisfied yet. In this paper, more than 80,000 paper abstracts in the built environment field were obtained to build a knowledge graph, a knowledge base storing entities and their connective relations in a graph-structured data model. To ensure the retrieval accuracy of the entities and relations in the knowledge graph, two well-annotated datasets have been created, containing 2,000 instances and 1,450 instances each in 29 relations for the named entity recognition task and relation extraction task respectively. These two tasks were solved by two BERT-based models trained on the proposed dataset. Both models attained an accuracy above 85% on these two tasks. More than 200,000 high-quality relations and entities were obtained using these models to extract all abstract data. Finally, this knowledge graph is presented as a self-developed visualization system to reveal relations between various entities in the domain. Both the source code and the annotated dataset can be found here: https://github.com/HKUST-KnowComp/BEKG.
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诸如“玻璃可以用于饮用水”之类的先决条件的推理仍然是语言模型的开放问题。主要的挑战在于,前提数据的稀缺性以及模型对这种推理的缺乏支持。我们提出了粉红色的,预处理性的推论,并通过弱监督进行了改进的模型,用于通过最低限度的监督来推理前提条件。我们从经验和理论上表明,粉红色改善了基准的结果,该基准的重点是通过常识性知识的前提(高达40%的宏F1分数)进行推理。我们通过Pac-Bayesian信息分析,精确度量和消融研究进一步研究粉红色。
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随着信息技术的快速发展,在线平台已经产生了巨大的文本资源。作为一种特定形式的信息提取(即),事件提取(EE)由于其自动从人类语言提取事件的能力而增加了普及。但是,事件提取有限的文献调查。现有审查工作要么花费很多努力,用于描述各种方法的细节或专注于特定领域。本研究提供了全面概述了最先进的事件提取方法及其从文本的应用程序,包括闭域和开放式事件提取。这项调查的特点是它提供了适度复杂性的概要,避免涉及特定方法的太多细节。本研究侧重于讨论代表作品的常见角色,应用领域,优势和缺点,忽略各个方法的特殊性。最后,我们总结了常见问题,当前解决方案和未来的研究方向。我们希望这项工作能够帮助研究人员和从业者获得最近的事件提取的快速概述。
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Many NLP tasks can be regarded as a selection problem from a set of options, such as classification tasks, multi-choice question answering, etc. Textual entailment (TE) has been shown as the state-of-the-art (SOTA) approach to dealing with those selection problems. TE treats input texts as premises (P), options as hypotheses (H), then handles the selection problem by modeling (P, H) pairwise. Two limitations: first, the pairwise modeling is unaware of other options, which is less intuitive since humans often determine the best options by comparing competing candidates; second, the inference process of pairwise TE is time-consuming, especially when the option space is large. To deal with the two issues, this work first proposes a contextualized TE model (Context-TE) by appending other k options as the context of the current (P, H) modeling. Context-TE is able to learn more reliable decision for the H since it considers various context. Second, we speed up Context-TE by coming up with Parallel-TE, which learns the decisions of multiple options simultaneously. Parallel-TE significantly improves the inference speed while keeping comparable performance with Context-TE. Our methods are evaluated on three tasks (ultra-fine entity typing, intent detection and multi-choice QA) that are typical selection problems with different sizes of options. Experiments show our models set new SOTA performance; particularly, Parallel-TE is faster than the pairwise TE by k times in inference. Our code is publicly available at https://github.com/jiangshdd/LearningToSelect.
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我们提出了一个零射门学习关系分类(ZSLRC)框架,通过其识别训练数据中不存在的新颖关系的能力来提高最先进的框架。零射击学习方法模仿人类学习和识别新概念的方式,没有先前的知识。为此,ZSLRC使用修改的高级原型网络来利用加权侧(辅助)信息。 ZSLRC的侧面信息是由关键字,名称实体的高度和标签及其同义词构建的。 ZSLRC还包括一个自动高义的提取框架,可直接从Web获取各种名称实体的高型。 ZSLRC提高了最先进的少量学习关系分类方法,依赖于标记的培训数据,因此即使在现实世界方案中也适用于某些关系对相应标记的培训示例。我们在两种公共数据集(NYT和NEREREL)上使用广泛的实验显示结果,并显示ZSLRC显着优于最先进的方法对监督学习,少量学习和零射击学习任务。我们的实验结果还展示了我们所提出的模型的有效性和稳健性。
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