手套通过利用来自Word Co-Feationence矩阵的统计信息来学习Word Embeddings。然而,矩阵中的字对对从预定义的本地上下文窗口中提取,这可能导致有限的字对对和潜在的语义无关词对。在本文中,我们提出了Semglove,其中从伯爵蒸馏到静态手套单词嵌入。特别是,我们提出了两种模型来提取基于屏蔽语言模型或伯特的多针注意重量的共发生统计。我们的方法可以在不受本地窗口假设的情况下提取字对对,并且可以通过直接考虑词对之间的语义距离来定义共发生权重。几个单词相似性数据集和四个外部任务的实验表明semglove可以优于手套。
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与伯特(Bert)等语言模型相比,已证明知识增强语言表示的预培训模型在知识基础构建任务(即〜关系提取)中更有效。这些知识增强的语言模型将知识纳入预训练中,以生成实体或关系的表示。但是,现有方法通常用单独的嵌入表示每个实体。结果,这些方法难以代表播出的实体和大量参数,在其基础代币模型之上(即〜变压器),必须使用,并且可以处理的实体数量为由于内存限制,实践限制。此外,现有模型仍然难以同时代表实体和关系。为了解决这些问题,我们提出了一个新的预培训模型,该模型分别从图书中学习实体和关系的表示形式,并分别在文本中跨越跨度。通过使用SPAN模块有效地编码跨度,我们的模型可以代表实体及其关系,但所需的参数比现有模型更少。我们通过从Wikipedia中提取的知识图对我们的模型进行了预训练,并在广泛的监督和无监督的信息提取任务上进行了测试。结果表明,我们的模型比基线学习对实体和关系的表现更好,而在监督的设置中,微调我们的模型始终优于罗伯塔,并在信息提取任务上取得了竞争成果。
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Neural language representation models such as BERT pre-trained on large-scale corpora can well capture rich semantic patterns from plain text, and be fine-tuned to consistently improve the performance of various NLP tasks. However, the existing pre-trained language models rarely consider incorporating knowledge graphs (KGs), which can provide rich structured knowledge facts for better language understanding. We argue that informative entities in KGs can enhance language representation with external knowledge. In this paper, we utilize both large-scale textual corpora and KGs to train an enhanced language representation model (ERNIE), which can take full advantage of lexical, syntactic, and knowledge information simultaneously. The experimental results have demonstrated that ERNIE achieves significant improvements on various knowledge-driven tasks, and meanwhile is comparable with the state-of-the-art model BERT on other common NLP tasks. The source code and experiment details of this paper can be obtained from https:// github.com/thunlp/ERNIE.
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Transformer-based models have pushed state of the art in many areas of NLP, but our understanding of what is behind their success is still limited. This paper is the first survey of over 150 studies of the popular BERT model. We review the current state of knowledge about how BERT works, what kind of information it learns and how it is represented, common modifications to its training objectives and architecture, the overparameterization issue and approaches to compression. We then outline directions for future research.
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We introduce a new language representation model called BERT, which stands for Bidirectional Encoder Representations from Transformers. Unlike recent language representation models (Peters et al., 2018a;Radford et al., 2018), BERT is designed to pretrain deep bidirectional representations from unlabeled text by jointly conditioning on both left and right context in all layers. As a result, the pre-trained BERT model can be finetuned with just one additional output layer to create state-of-the-art models for a wide range of tasks, such as question answering and language inference, without substantial taskspecific architecture modifications.BERT is conceptually simple and empirically powerful. It obtains new state-of-the-art results on eleven natural language processing tasks, including pushing the GLUE score to 80.5% (7.7% point absolute improvement), MultiNLI accuracy to 86.7% (4.6% absolute improvement), SQuAD v1.1 question answering Test F1 to 93.2 (1.5 point absolute improvement) and SQuAD v2.0 Test F1 to 83.1 (5.1 point absolute improvement).
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在培训数据中拟合复杂的模式,例如推理和争议,是语言预训练的关键挑战。根据最近的研究和我们的经验观察,一种可能的原因是训练数据中的一些易于适应的模式,例如经常共同发生的单词组合,主导和伤害预训练,使模型很难适合更复杂的信息。我们争辩说,错误预测可以帮助找到危害语言理解的这种主导模式。当发生错误预测时,应该经常与导致MIS预测的模型拟合的MIS预测字相同的模式。如果我们可以添加正规化以培训模型,当MIS预测发生并更多地对待更微妙的模式时,可以在更多信息上缩小到这种主导模式时,可以在预训练中有效地安装更多信息。在此动机之后,我们提出了一种新的语言预培训方法,错误预测作为伤害警报(MPA)。在MPA中,当在预训练期间发生错误预测时,我们使用其共同发生信息来指导自我关注模块的多个头部。变压器模块中的一些自我关注头经过优化,以将更低的注意重量分配给频繁地在误报中的输入句子中的单词,同时将更高权重分配给另一个单词。通过这样做,变压器模型训练,以依赖于主导的频繁共同发生模式,而在误报中,当发生错误预测时,在剩余更复杂的信息上更加关注更多。我们的实验表明,MPA加快了伯特和电器的预训练,并提高了他们对下游任务的表现。
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近年来BERT显示明显的优势,在自然语言处理任务的巨大潜力。然而,培训和应用BERT需要计算上下文语言表示,这阻碍了它的普遍性和适用性密集的时间和资源。为了克服这个瓶颈,我们采用窗口屏蔽机制立正层提出了深刻的双向语言模型。这项工作计算上下文的语言表示,而没有随意屏蔽一样在BERT和保持深双向架构类似BERT。为了计算相同的句子表示,我们的方法显示出O(n)的复杂性相比少其他基于变压器的型号O($ N ^ $ 2)。为了进一步显示其优越性,计算在CPU环境背景下的语言表述中进行,通过短信分类方面使用的嵌入,从所提出的方法,logistic回归显示更高的精度。 Moverover,所提出的方法也实现了语义相似任务显著更高的性能。
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语言模型中的上下文化单词嵌入已为NLP提供了很大的进步。直观地,句子信息集成到单词的表示中,这可以帮助模型多义。但是,上下文灵敏度也导致表示形式的差异,这可能会破坏同义词的语义一致性。我们量化了典型的预训练模型中每个单词sense的上下文嵌入的程度各不相同。结果表明,在上下文中,上下文化的嵌入可以高度一致。此外,词性,单词感官的数量和句子长度对感官表示的差异有影响。有趣的是,我们发现单词表示是偏见的,在不同上下文中的第一个单词往往更相似。我们分析了这种现象,还提出了一种简单的方法来减轻基于距离的单词sense剥夺歧义设置的偏见。
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用于预培训语言模型的自我监督学习的核心包括预训练任务设计以及适当的数据增强。语言模型中的大多数数据增强都是独立于上下文的。最近在电子中提出了一个开创性的增强,并通过引入辅助生成网络(发电机)来实现最先进的性能,以产生用于培训主要辨别网络(鉴别者)的上下文化数据增强。然而,这种设计引入了发电机的额外计算成本,并且需要调整发电机和鉴别器之间的相对能力。在本文中,我们提出了一种自增强策略(SAS),其中单个网络用于审视以后的时期的培训常规预训练和上下文化数据增强。基本上,该策略消除了单独的发电机,并使用单个网络共同执行具有MLM(屏蔽语言建模)和RTD(替换令牌检测)头的两个预训练任务。它避免了寻找适当大小的发电机的挑战,这对于在电子中证明的性能至关重要,以及其随后的变体模型至关重要。此外,SAS是一项常规策略,可以与最近或将来的许多新技术无缝地结合,例如杜伯塔省的解除关注机制。我们的实验表明,SAS能够在具有相似或更少的计算成本中优于胶水任务中的电磁和其他最先进的模型。
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事实证明,将先验知识纳入预训练的语言模型中对知识驱动的NLP任务有效,例如实体键入和关系提取。当前的培训程序通常通过使用知识掩盖,知识融合和知识更换将外部知识注入模型。但是,输入句子中包含的事实信息尚未完全开采,并且尚未严格检查注射的外部知识。结果,无法完全利用上下文信息,并将引入额外的噪音,或者注入的知识量受到限制。为了解决这些问题,我们提出了MLRIP,该MLRIP修改了Ernie-Baidu提出的知识掩盖策略,并引入了两阶段的实体替代策略。进行全面分析的广泛实验说明了MLRIP在军事知识驱动的NLP任务中基于BERT的模型的优势。
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近年来,基于变压器的预训练模型已获得了很大的进步,成为自然语言处理中最重要的骨干之一。最近的工作表明,变压器内部的注意力机制可能不需要,卷积神经网络和基于多层感知器的模型也已被研究为变压器替代方案。在本文中,我们考虑了一个用于语言模型预训练的图形循环网络,该网络通过本地令牌级通信为每个序列构建一个图形结构,以及与其他代币解耦的句子级表示。原始模型在受监督培训下的特定领域特定文本分类中表现良好,但是,其通过自我监督的方式学习转移知识的潜力尚未得到充分利用。我们通过优化体系结构并验证其在更通用的语言理解任务(英语和中文)中的有效性来填补这一空白。至于模型效率,我们的模型在基于变压器的模型中而不是二次复杂性,而是具有线性复杂性,并且在推断过程中的性能更有效。此外,我们发现与现有基于注意力的模型相比,我们的模型可以生成更多样化的输出,而背景化的功能冗余性较小。
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Cloze任务是一种广泛使用的任务,可以评估NLP系统的语言理解能力。然而,大多数现有的渗透任务只需要NLP系统以提供每个输入数据样本的相对最佳预测,而不是在输入域中以一致的方式以一致的方式为所有可能的预测的绝对质量。因此,提出了一种新的任务:预测填充任务中的填充词是一个好的,中立或坏候选者。可以扩展复杂的版本以预测更多离散类或连续分数。我们专注于Semoval 2022任务7的子任务,探讨了一些可能的架构来解决这一新任务,提供了对它们的详细比较,并提出了一种在这项新任务中改进传统模型的集合方法。
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Language model pre-training, such as BERT, has significantly improved the performances of many natural language processing tasks. However, pre-trained language models are usually computationally expensive, so it is difficult to efficiently execute them on resourcerestricted devices. To accelerate inference and reduce model size while maintaining accuracy, we first propose a novel Transformer distillation method that is specially designed for knowledge distillation (KD) of the Transformer-based models. By leveraging this new KD method, the plenty of knowledge encoded in a large "teacher" BERT can be effectively transferred to a small "student" Tiny-BERT. Then, we introduce a new two-stage learning framework for TinyBERT, which performs Transformer distillation at both the pretraining and task-specific learning stages. This framework ensures that TinyBERT can capture the general-domain as well as the task-specific knowledge in BERT. TinyBERT 41 with 4 layers is empirically effective and achieves more than 96.8% the performance of its teacher BERT BASE on GLUE benchmark, while being 7.5x smaller and 9.4x faster on inference. TinyBERT 4 is also significantly better than 4-layer state-of-the-art baselines on BERT distillation, with only ∼28% parameters and ∼31% inference time of them. Moreover, TinyBERT 6 with 6 layers performs on-par with its teacher BERT BASE .
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预训练的语言模型(PLM)在自然语言理解中的许多下游任务中取得了显着的性能增长。已提出了各种中文PLM,以学习更好的中文表示。但是,大多数当前模型都使用中文字符作为输入,并且无法编码中文单词中包含的语义信息。虽然最近的预训练模型同时融合了单词和字符,但它们通常会遭受不足的语义互动,并且无法捕获单词和字符之间的语义关系。为了解决上述问题,我们提出了一个简单而有效的PLM小扣手,该小扣子采用了对单词和性格表示的对比度学习。特别是,Clower通过对多透明信息的对比学习将粗粒的信息(即单词)隐式编码为细粒度表示(即字符)。在现实的情况下,小电动器具有很大的价值,因为它可以轻松地将其纳入任何现有的基于细粒的PLM中而无需修改生产管道。在一系列下游任务上进行的扩展实验表明,小动物的卓越性能超过了几个最先进的实验 - 艺术基线。
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在生物医学语料库中预先培训的语言模型,例如Biobert,最近在下游生物医学任务上显示出令人鼓舞的结果。另一方面,由于嵌入尺寸,隐藏尺寸和层数等因素,许多现有的预训练模型在资源密集型和计算上都是沉重的。自然语言处理(NLP)社区已经制定了许多策略来压缩这些模型,利用修剪,定量和知识蒸馏等技术,从而导致模型更快,更小,随后更易于使用。同样,在本文中,我们介绍了六种轻型模型,即Biodistilbert,Biotinybert,BioMobilebert,Distilbiobert,Tinybiobert和Cmpactactbiobert,并通过掩护的语言在PubMed DataSet上通过掩护数据进行了知识蒸馏而获得的知识蒸馏来获得。建模(MLM)目标。我们在三个生物医学任务上评估了所有模型,并将它们与Biobert-V1.1进行比较,以创建有效的轻量级模型,以与较大的对应物相同。所有模型将在我们的HuggingFace配置文件上公开可用,网址为https://huggingface.co/nlpie,用于运行实验的代码将在https://github.com/nlpie-research/compact-compact-biomedical-transformers上获得。
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Natural Language Understanding has seen an increasing number of publications in the last few years, especially after robust word embeddings models became prominent, when they proved themselves able to capture and represent semantic relationships from massive amounts of data. Nevertheless, traditional models often fall short in intrinsic issues of linguistics, such as polysemy and homonymy. Any expert system that makes use of natural language in its core, can be affected by a weak semantic representation of text, resulting in inaccurate outcomes based on poor decisions. To mitigate such issues, we propose a novel approach called Most Suitable Sense Annotation (MSSA), that disambiguates and annotates each word by its specific sense, considering the semantic effects of its context. Our approach brings three main contributions to the semantic representation scenario: (i) an unsupervised technique that disambiguates and annotates words by their senses, (ii) a multi-sense embeddings model that can be extended to any traditional word embeddings algorithm, and (iii) a recurrent methodology that allows our models to be re-used and their representations refined. We test our approach on six different benchmarks for the word similarity task, showing that our approach can produce state-of-the-art results and outperforms several more complex state-of-the-art systems.
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多语言语言模型(\ mllms),如mbert,xlm,xlm-r,\ textit {etc。}已成为一种可行的选择,使预先估计到大量语言的力量。鉴于他们的成功在零射击转移学习中,在(i)建立更大的\ mllms〜覆盖了大量语言(ii)创建覆盖更广泛的任务和语言来评估的详尽工作基准mllms〜(iii)分析单音零点,零拍摄交叉和双语任务(iv)对Monolingual的性能,了解\ mllms〜(v)增强(通常)学习的通用语言模式(如果有的话)有限的容量\ mllms〜以提高他们在已见甚至看不见语言的表现。在这项调查中,我们审查了现有的文学,涵盖了上述与\ MLLMS有关的广泛研究领域。根据我们的调查,我们建议您有一些未来的研究方向。
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Recent progress in pre-trained neural language models has significantly improved the performance of many natural language processing (NLP) tasks. In this paper we propose a new model architecture DeBERTa (Decoding-enhanced BERT with disentangled attention) that improves the BERT and RoBERTa models using two novel techniques. The first is the disentangled attention mechanism, where each word is represented using two vectors that encode its content and position, respectively, and the attention weights among words are computed using disentangled matrices on their contents and relative positions, respectively. Second, an enhanced mask decoder is used to incorporate absolute positions in the decoding layer to predict the masked tokens in model pre-training. In addition, a new virtual adversarial training method is used for fine-tuning to improve models' generalization. We show that these techniques significantly improve the efficiency of model pre-training and the performance of both natural language understand (NLU) and natural langauge generation (NLG) downstream tasks. Compared to RoBERTa-Large, a DeBERTa model trained on half of the training data performs consistently better on a wide range of NLP tasks, achieving improvements on MNLI by +0.9% (90.2% vs. 91.1%), on SQuAD v2.0 by +2.3% (88.4% vs. 90.7%) and RACE by +3.6% (83.2% vs. 86.8%). Notably, we scale up DeBERTa by training a larger version that consists of 48 Transform layers with 1.5 billion parameters. The significant performance boost makes the single DeBERTa model surpass the human performance on the SuperGLUE benchmark (Wang et al., 2019a) for the first time in terms of macro-average score (89.9 versus 89.8), and the ensemble DeBERTa model sits atop the SuperGLUE leaderboard as of January 6, 2021, outperforming the human baseline by a decent margin (90.3 versus 89.8). The pre-trained DeBERTa models and the source code were released at: https://github.com/microsoft/DeBERTa 1 .
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The relationship between words in a sentence often tells us more about the underlying semantic content of a document than its actual words, individually. In this work, we propose two novel algorithms, called Flexible Lexical Chain II and Fixed Lexical Chain II. These algorithms combine the semantic relations derived from lexical chains, prior knowledge from lexical databases, and the robustness of the distributional hypothesis in word embeddings as building blocks forming a single system. In short, our approach has three main contributions: (i) a set of techniques that fully integrate word embeddings and lexical chains; (ii) a more robust semantic representation that considers the latent relation between words in a document; and (iii) lightweight word embeddings models that can be extended to any natural language task. We intend to assess the knowledge of pre-trained models to evaluate their robustness in the document classification task. The proposed techniques are tested against seven word embeddings algorithms using five different machine learning classifiers over six scenarios in the document classification task. Our results show the integration between lexical chains and word embeddings representations sustain state-of-the-art results, even against more complex systems.
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来自文本的采矿因果关系是一种复杂的和至关重要的自然语言理解任务,对应于人类认知。其解决方案的现有研究可以分为两种主要类别:基于特征工程和基于神经模型的方法。在本文中,我们发现前者具有不完整的覆盖范围和固有的错误,但提供了先验知识;虽然后者利用上下文信息,但其因果推断不足。为了处理限制,我们提出了一个名为MCDN的新型因果关系检测模型,明确地模拟因果关系,而且,利用两种方法的优势。具体而言,我们采用多头自我关注在Word级别获得语义特征,并在段级别推断出来的SCRN。据我们所知,关于因果关系任务,这是第一次应用关系网络。实验结果表明:1)该方法对因果区检测进行了突出的性能; 2)进一步分析表现出MCDN的有效性和稳健性。
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