This paper presents a new UNIfied pre-trained Language Model (UNILM) that can be fine-tuned for both natural language understanding and generation tasks. The model is pre-trained using three types of language modeling tasks: unidirectional, bidirectional, and sequence-to-sequence prediction. The unified modeling is achieved by employing a shared Transformer network and utilizing specific self-attention masks to control what context the prediction conditions on. UNILM compares favorably with BERT on the GLUE benchmark, and the SQuAD 2.0 and CoQA question answering tasks. Moreover, UNILM achieves new state-ofthe-art results on five natural language generation datasets, including improving the CNN/DailyMail abstractive summarization ROUGE-L to 40.51 (2.04 absolute improvement), the Gigaword abstractive summarization ROUGE-L to 35.75 (0.86 absolute improvement), the CoQA generative question answering F1 score to 82.5 (37.1 absolute improvement), the SQuAD question generation BLEU-4 to 22.12 (3.75 absolute improvement), and the DSTC7 document-grounded dialog response generation NIST-4 to 2.67 (human performance is 2.65). The code and pre-trained models are available at https://github.com/microsoft/unilm. * Equal contribution. † Contact person.
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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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问题答案(QA)是自然语言处理中最具挑战性的最具挑战性的问题之一(NLP)。问答(QA)系统试图为给定问题产生答案。这些答案可以从非结构化或结构化文本生成。因此,QA被认为是可以用于评估文本了解系统的重要研究区域。大量的QA研究致力于英语语言,调查最先进的技术和实现最先进的结果。然而,由于阿拉伯QA中的研究努力和缺乏大型基准数据集,在阿拉伯语问答进展中的研究努力得到了很大速度的速度。最近许多预先接受的语言模型在许多阿拉伯语NLP问题中提供了高性能。在这项工作中,我们使用四个阅读理解数据集来评估阿拉伯QA的最先进的接种变压器模型,它是阿拉伯语 - 队,ArcD,AQAD和TYDIQA-GoldP数据集。我们微调并比较了Arabertv2基础模型,ArabertV0.2大型型号和ARAElectra模型的性能。在最后,我们提供了一个分析,了解和解释某些型号获得的低绩效结果。
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We present BART, a denoising autoencoder for pretraining sequence-to-sequence models. BART is trained by ( 1) corrupting text with an arbitrary noising function, and (2) learning a model to reconstruct the original text. It uses a standard Tranformer-based neural machine translation architecture which, despite its simplicity, can be seen as generalizing BERT (due to the bidirectional encoder), GPT (with the left-to-right decoder), and many other more recent pretraining schemes. We evaluate a number of noising approaches, finding the best performance by both randomly shuffling the order of the original sentences and using a novel in-filling scheme, where spans of text are replaced with a single mask token. BART is particularly effective when fine tuned for text generation but also works well for comprehension tasks. It matches the performance of RoBERTa with comparable training resources on GLUE and SQuAD, achieves new stateof-the-art results on a range of abstractive dialogue, question answering, and summarization tasks, with gains of up to 6 ROUGE. BART also provides a 1.1 BLEU increase over a back-translation system for machine translation, with only target language pretraining. We also report ablation experiments that replicate other pretraining schemes within the BART framework, to better measure which factors most influence end-task performance.
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We present SpanBERT, a pre-training method that is designed to better represent and predict spans of text. Our approach extends BERT by (1) masking contiguous random spans, rather than random tokens, and (2) training the span boundary representations to predict the entire content of the masked span, without relying on the individual token representations within it. Span-BERT consistently outperforms BERT and our better-tuned baselines, with substantial gains on span selection tasks such as question answering and coreference resolution. In particular, with the same training data and model size as BERT large , our single model obtains 94.6% and 88.7% F1 on SQuAD 1.1 and 2.0 respectively. We also achieve a new state of the art on the OntoNotes coreference resolution task (79.6% F1), strong performance on the TACRED relation extraction benchmark, and even gains on GLUE. 1 * Equal contribution. 1 Our code and pre-trained models are available at https://github.com/facebookresearch/ SpanBERT.
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在本文中,我们利用了以前的预训练模型(PTM)的优势,并提出了一种新型的中国预训练的不平衡变压器(CPT)。与以前的中国PTM不同,CPT旨在利用自然语言理解(NLU)和自然语言生成(NLG)之间的共同知识来促进表现。 CPT包括三个部分:共享编码器,一个理解解码器和一代解码器。具有共享编码器的两个特定解码器分别通过蒙版语言建模(MLM)进行了预训练,并分别将自动编码(DAE)任务进行了验证。借助部分共享的体系结构和多任务预培训,CPT可以(1)使用两个解码器学习NLU或NLG任务的特定知识,并且(2)对模型的潜力充分利用了微调。此外,不平衡的变压器节省了计算和存储成本,这使CPT竞争激烈,并极大地加速了文本生成的推断。对各种中国NLU和NLG任务的实验结果显示了CPT的有效性。
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基础模型由于在广泛的下游应用中的有效性而受到了很多关注。尽管在体系结构方面存在很大的融合,但大多数审慎的模型通常仍用于特定任务或模式。在这项工作中,我们建议将语言模型用作各种基础模型的通用接口。一系列预处理的编码者感知到了多种方式(例如视觉和语言),并与扮演通用任务层角色的语言模型对接。我们提出了一个半伴侣的语言建模目标,以共同确定界面和模块化编码器。我们从因果关系和非因果建模中涵盖了优势和能力,从而结合了两个世界的最佳状态。具体而言,所提出的方法不仅从因果语言建模中继承了内在学习和开放式生成的能力,而且由于双向编码器而有利于填补。更重要的是,我们的方法无缝地解锁了上述功能的组合,例如,通过填充编码器启用了文本学习或指导。各种仅语言和视觉语言基准的实验结果表明,我们的模型表现优于或与鉴定,零弹性概括和几乎没有的学习的专业模型竞争。
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Bidirectional Encoder Representations from Transformers (BERT; Devlin et al. 2019) represents the latest incarnation of pretrained language models which have recently advanced a wide range of natural language processing tasks. In this paper, we showcase how BERT can be usefully applied in text summarization and propose a general framework for both extractive and abstractive models. We introduce a novel document-level encoder based on BERT which is able to express the semantics of a document and obtain representations for its sentences. Our extractive model is built on top of this encoder by stacking several intersentence Transformer layers. For abstractive summarization, we propose a new fine-tuning schedule which adopts different optimizers for the encoder and the decoder as a means of alleviating the mismatch between the two (the former is pretrained while the latter is not). We also demonstrate that a two-staged fine-tuning approach can further boost the quality of the generated summaries. Experiments on three datasets show that our model achieves stateof-the-art results across the board in both extractive and abstractive settings. 1
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查询聚焦的文本摘要(QFTS)任务旨在构建基于给定查询的文本文档摘要的构建系统。解决此任务的关键挑战是缺乏培训摘要模型的大量标记数据。在本文中,我们通过探索一系列域适应技术来解决这一挑战。鉴于最近在广泛的自然语言处理任务中进行预先接受的变压器模型的成功,我们利用此类模型为单文档和多文件方案的QFTS任务产生抽象摘要。对于域适应,我们使用预先训练的变压器的摘要模型应用了各种技术,包括转移学习,弱监督学习和远程监督。六个数据集的广泛实验表明,我们所提出的方法非常有效地为QFTS任务产生抽象摘要,同时在一组自动和人类评估指标上设置新的最先进的结果。
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This paper presents a unified Vision-Language Pre-training (VLP) model. The model is unified in that (1) it can be finetuned for either vision-language generation (e.g., image captioning) or understanding (e.g., visual question answering) tasks, and (2) it uses a shared multi-layer transformer network for both encoding and decoding, which differs from many existing methods where the encoder and decoder are implemented using separate models. The unified VLP model is pre-trained on a large amount of image-text pairs using the unsupervised learning objectives of two tasks: bidirectional and sequence-to-sequence (seq2seq) masked vision-language prediction. The two tasks differ solely in what context the prediction conditions on. This is controlled by utilizing specific self-attention masks for the shared transformer network. To the best of our knowledge, VLP is the first reported model that achieves state-of-the-art results on both vision-language generation and understanding tasks, as disparate as image captioning and visual question answering, across three challenging benchmark datasets: COCO Captions, Flickr30k Captions, and VQA 2.0. The code and the pre-trained models are available at https://github.com/LuoweiZhou/VLP.
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本文介绍了Z-Code ++,这是一种针对抽象文本摘要优化的新的预训练的语言模型。该模型使用三种技术扩展了艺术编码器模型的状态。首先,我们使用两阶段的预训练过程来改善模型在低资源摘要任务上的性能。该模型首先是使用文本语料库进行语言理解的预先培训的,然后在汇总语料库中不断预先培训,以进行基础文本生成。其次,我们用分离的注意力层代替编码器中的自我发项层,其中每个单词都使用两个向量分别代表其内容和位置。第三,我们使用融合编码器,这是一种以层次方式编码长序列的简单而有效的方法。 Z-Code ++在13个文本摘要任务中的9个跨5种语言中创建了新的艺术状态。我们的模型的参数有效,因为它的表现优于XSUM上600倍较大的Palm-540b,并且在Samsum上的易经的200倍GPT3-175B较大。在零射击和少量设置中,我们的模型大大优于竞争模型。
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本文提出了一种新的预先接受训练的语言模型Debertav3,它通过用更换的令牌检测(RTD)更换掩模语言建模(MLM)来改善原始的Deberta模型,更高的预训练任务。我们的分析表明,Vanilla嵌入了电力中的共享损害培训效率和模型性能。这是因为鉴别器的培训损失和发电机的销售损失在不同的方向上拉动令牌嵌入,从而创造“拔河”动态。因此,我们提出了一种新的梯度 - 解开嵌入共享方法,避免了战争动态,提高了训练效率和预训练模型的质量。我们使用与Deberta相同的设置预先接受了培训的Debertav3,以展示其在广泛的下游自然语言理解(NLU)任务上的特殊表现。以八个任务为例,Debertav3大型模型以八个任务为例,平均得分为91.37%,杜伯塔省的1.37%和电力1.91%,在模型中设置新的最先进(SOTA)具有类似的结构。此外,我们预先培训了多语思伯类Mdeberta,与英语模型相比,对强基线的更大改善。例如,Mdeberta基地达到XNLI的79.8%零射频精度和超过XLM-R基础的3.6%的改进,在此基准上创建了一个新的Sota。我们在HTTPS://github.com/microsoft/deberta公开提供我们预先接受的模型和推理码。
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在这项工作中,我们探索如何学习专用的语言模型,旨在学习从文本文件中学习关键词的丰富表示。我们在判别和生成设置中进行预训练变压器语言模型(LMS)的不同掩蔽策略。在歧视性设定中,我们引入了一种新的预训练目标 - 关键边界,用替换(kbir)infifiling,在使用Kbir预先训练的LM进行微调时显示出在Sota上的性能(F1中高达9.26点)的大量增益关键酶提取的任务。在生成设置中,我们为BART - 键盘介绍了一个新的预训练设置,可再现与CATSeq格式中的输入文本相关的关键字,而不是Denoised原始输入。这也导致在关键词中的性能(F1 @ M)中的性能(高达4.33点),用于关键正版生成。此外,我们还微调了在命名实体识别(ner),问题应答(qa),关系提取(重新),抽象摘要和达到与SOTA的可比性表现的预训练的语言模型,表明学习丰富的代表关键词确实有利于许多其他基本的NLP任务。
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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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GPT-2和BERT展示了在各种自然语言处理任务上使用预训练的语言模型(LMS)的有效性。但是,在应用于资源丰富的任务时,LM微调通常会遭受灾难性的遗忘。在这项工作中,我们引入了一个协同的培训框架(CTNMT),该框架是将预训练的LMS集成到神经机器翻译(NMT)的关键。我们提出的CTNMT包括三种技术:a)渐近蒸馏,以确保NMT模型可以保留先前的预训练知识; b)动态的开关门,以避免灾难性忘记预训练的知识; c)根据计划的政策调整学习步伐的策略。我们在机器翻译中的实验表明,WMT14英语 - 德语对的CTNMT获得了最高3个BLEU得分,甚至超过了先前的最先进的预培训辅助NMT NMT的NMT。尽管对于大型WMT14英语法国任务,有400万句话,但我们的基本模型仍然可以显着改善最先进的变压器大型模型,超过1个BLEU得分。代码和模型可以从https://github.com/bytedance/neurst/tree/Master/Master/examples/ctnmt下载。
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Entities, as important carriers of real-world knowledge, play a key role in many NLP tasks. We focus on incorporating entity knowledge into an encoder-decoder framework for informative text generation. Existing approaches tried to index, retrieve, and read external documents as evidence, but they suffered from a large computational overhead. In this work, we propose an encoder-decoder framework with an entity memory, namely EDMem. The entity knowledge is stored in the memory as latent representations, and the memory is pre-trained on Wikipedia along with encoder-decoder parameters. To precisely generate entity names, we design three decoding methods to constrain entity generation by linking entities in the memory. EDMem is a unified framework that can be used on various entity-intensive question answering and generation tasks. Extensive experimental results show that EDMem outperforms both memory-based auto-encoder models and non-memory encoder-decoder models.
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Pre-trained models have achieved remarkable success in natural language processing (NLP). However, existing pre-training methods underutilize the benefits of language understanding for generation. Inspired by the idea of Generative Adversarial Networks (GANs), we propose a GAN-style model for encoder-decoder pre-training by introducing an auxiliary discriminator, unifying the ability of language understanding and generation in a single model. Our model, named as GanLM, is trained with two pre-training objectives: replaced token detection and replaced token denoising. Specifically, given masked source sentences, the generator outputs the target distribution and the discriminator predicts whether the target sampled tokens from distribution are incorrect. The target sentence is replaced with misclassified tokens to construct noisy previous context, which is used to generate the gold sentence. In general, both tasks improve the ability of language understanding and generation by selectively using the denoising data. Extensive experiments in language generation benchmarks show that GanLM with the powerful language understanding capability outperforms various strong pre-trained language models (PLMs) and achieves state-of-the-art performance.
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Transfer learning, where a model is first pre-trained on a data-rich task before being finetuned on a downstream task, has emerged as a powerful technique in natural language processing (NLP). The effectiveness of transfer learning has given rise to a diversity of approaches, methodology, and practice. In this paper, we explore the landscape of transfer learning techniques for NLP by introducing a unified framework that converts all text-based language problems into a text-to-text format. Our systematic study compares pre-training objectives, architectures, unlabeled data sets, transfer approaches, and other factors on dozens of language understanding tasks. By combining the insights from our exploration with scale and our new "Colossal Clean Crawled Corpus", we achieve state-of-the-art results on many benchmarks covering summarization, question answering, text classification, and more. To facilitate future work on transfer learning for NLP, we release our data set, pre-trained models, and code.
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以查询为中心的摘要(QFS)旨在产生应答感兴趣的特定问题的摘要,从而实现更大的用户控制和个性化。虽然最近发布的数据集如QMSUM或Aquamuse,促进QFS中的研究工作,但该领域缺乏对适用建模方法的广泛空间的全面研究。在本文中,考虑到两种普遍的方法,我们对QFS进行了系统探索,探讨了QFS:两阶段的采掘解决方案和端到端模型。在这些类别中,我们调查现有方法,并呈现了在QMSUM数据集上实现最先进的性能的两个模型扩展,其边缘高达3.38 Rouge-1,3.72 Rouge-2和3.28 Rouge-L。通过定量实验,我们突出了不同模型配置之间的权衡,并探讨了摘要任务之间的转移能力。代码和检查点公开可用:https://github.com/salesforce/query-focused-sum。
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近年来,在应用预训练的语言模型(例如Bert)上,取得了巨大进展,以获取信息检索(IR)任务。在网页中通常使用的超链接已被利用用于设计预训练目标。例如,超链接的锚文本已用于模拟查询,从而构建了巨大的查询文档对以进行预训练。但是,作为跨越两个网页的桥梁,尚未完全探索超链接的潜力。在这项工作中,我们专注于建模通过超链接连接的两个文档之间的关系,并为临时检索设计一个新的预训练目标。具体而言,我们将文档之间的关系分为四组:无链接,单向链接,对称链接和最相关的对称链接。通过比较从相邻组采样的两个文档,该模型可以逐渐提高其捕获匹配信号的能力。我们提出了一个渐进的超链接预测({php})框架,以探索预训练中超链接的利用。对两个大规模临时检索数据集和六个提问数据集的实验结果证明了其优于现有的预训练方法。
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