面向目标的意见单词提取(TOWE)是一项精细的情感分析任务,旨在从句子中提取给定意见目标的相应意见单词。最近,深度学习方法在这项任务上取得了显着进步。然而,由于昂贵的数据注释过程,TOWE任务仍然遭受培训数据的稀缺性。有限的标记数据增加了测试数据和培训数据之间分配变化的风险。在本文中,我们建议利用大量未标记的数据来通过增加模型对变化分布变化的暴露来降低风险。具体而言,我们提出了一种新型的多透明一致性正则化(MGCR)方法,以利用未标记的数据并设计两个专门用于TOWE的过滤器,以在不同的粒度上过滤嘈杂的数据。四个TOWE基准数据集的广泛实验结果表明,与当前的最新方法相比,MGCR的优越性。深入分析还证明了不同粒度过滤器的有效性。我们的代码可在https://github.com/towessl/towessl上找到。
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半监督学习(SSL)通过利用大量未标记数据来增强有限标记的样品来改善模型的概括。但是,目前,流行的SSL评估协议通常受到计算机视觉(CV)任务的约束。此外,以前的工作通常从头开始训练深层神经网络,这是耗时且环境不友好的。为了解决上述问题,我们通过从简历,自然语言处理(NLP)和音频处理(AUDIO)中选择15种不同,具有挑战性和全面的任务来构建统一的SSL基准(USB),我们会系统地评估主导的SSL方法,以及开源的一个模块化和可扩展的代码库,以对这些SSL方法进行公平评估。我们进一步为简历任务提供了最新的神经模型的预训练版本,以使成本负担得起,以进行进一步调整。 USB启用对来自多个域的更多任务的单个SSL算法的评估,但成本较低。具体而言,在单个NVIDIA V100上,仅需要37个GPU天才能在USB中评估15个任务的FIXMATCH,而335 GPU天(除ImageNet以外的4个CV数据集中的279 GPU天)在使用典型协议的5个CV任务上需要进行5个CV任务。
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视觉识别任务中的长尾类分布对于如何处理头部和尾部类之间的偏置预测,即,模型倾向于将尾部类作为头部类进行分类。虽然现有的研究专注于数据重采采样和损失函数工程,但在本文中,我们采取了不同的视角:分类利润率。我们研究边距和注册之间的关系(分类得分)并经验遵守偏置边缘,并且偏置的Logits是正相关的。我们提出MARC,一个简单但有效的边缘校准函数,用于动态校准偏置边缘的偏置利润。我们通过对普通的长尾基准测试进行了广泛的实验,包括CIFAR-LT,Imagenet-LT,LT,以及不适物 - LT的广泛实验。实验结果表明,我们的MARC在这些基准上实现了有利的结果。此外,Marc只需三行代码即可实现。我们希望这种简单的方法能够激励人们重新思考偏置的边距和偏见的长尾视觉识别标识。
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交叉语言语音适应旨在解决利用多种丰富资源语言来构建低资源目标语言的模型的问题。由于低资源语言具有有限的培训数据,语音识别模型可以容易地过度装备。在本文中,我们建议使用适配器来研究多种适配器的性能,用于参数有效的交叉语音语音适应。基于我们以前的MetaAdapter,隐含地利用适配器,我们提出了一种名为SimAdapter的新算法,用于从Adapters明确学习知识。我们的算法利用了可以轻松集成到变压器结构中的适配器.METAADAPTER利用元学习将一般知识从训练数据转移到测试语言。 SimAdapter旨在使用适配器微调期间了解源语言与目标语言之间的相似性。我们在公共语音数据集中对五种低资源语言进行广泛的实验。结果表明,与强大的全型微调基线相比,我们的MetaAdapter和SimAdapter方法可以将WER减小2.98%和2.55%,只有2.5%和15.5%的培训参数。此外,我们还表明这两种新型算法可以集成,以便更好的性能,相对减少高达3.55%。
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In various fields of data science, researchers are often interested in estimating the ratio of conditional expectation functions (CEFR). Specifically in causal inference problems, it is sometimes natural to consider ratio-based treatment effects, such as odds ratios and hazard ratios, and even difference-based treatment effects are identified as CEFR in some empirically relevant settings. This chapter develops the general framework for estimation and inference on CEFR, which allows the use of flexible machine learning for infinite-dimensional nuisance parameters. In the first stage of the framework, the orthogonal signals are constructed using debiased machine learning techniques to mitigate the negative impacts of the regularization bias in the nuisance estimates on the target estimates. The signals are then combined with a novel series estimator tailored for CEFR. We derive the pointwise and uniform asymptotic results for estimation and inference on CEFR, including the validity of the Gaussian bootstrap, and provide low-level sufficient conditions to apply the proposed framework to some specific examples. We demonstrate the finite-sample performance of the series estimator constructed under the proposed framework by numerical simulations. Finally, we apply the proposed method to estimate the causal effect of the 401(k) program on household assets.
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Background and objective: COVID-19 and its variants have caused significant disruptions in over 200 countries and regions worldwide, affecting the health and lives of billions of people. Detecting COVID-19 from chest X-Ray (CXR) images has become one of the fastest and easiest methods for detecting COVID-19 since the common occurrence of radiological pneumonia findings in COVID-19 patients. We present a novel high-accuracy COVID-19 detection method that uses CXR images. Methods: Our method consists of two phases. One is self-supervised learning-based pertaining; the other is batch knowledge ensembling-based fine-tuning. Self-supervised learning-based pretraining can learn distinguished representations from CXR images without manually annotated labels. On the other hand, batch knowledge ensembling-based fine-tuning can utilize category knowledge of images in a batch according to their visual feature similarities to improve detection performance. Unlike our previous implementation, we introduce batch knowledge ensembling into the fine-tuning phase, reducing the memory used in self-supervised learning and improving COVID-19 detection accuracy. Results: On two public COVID-19 CXR datasets, namely, a large dataset and an unbalanced dataset, our method exhibited promising COVID-19 detection performance. Our method maintains high detection accuracy even when annotated CXR training images are reduced significantly (e.g., using only 10% of the original dataset). In addition, our method is insensitive to changes in hyperparameters. Conclusions: The proposed method outperforms other state-of-the-art COVID-19 detection methods in different settings. Our method can reduce the workloads of healthcare providers and radiologists.
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Purpose: Considering several patients screened due to COVID-19 pandemic, computer-aided detection has strong potential in assisting clinical workflow efficiency and reducing the incidence of infections among radiologists and healthcare providers. Since many confirmed COVID-19 cases present radiological findings of pneumonia, radiologic examinations can be useful for fast detection. Therefore, chest radiography can be used to fast screen COVID-19 during the patient triage, thereby determining the priority of patient's care to help saturated medical facilities in a pandemic situation. Methods: In this paper, we propose a new learning scheme called self-supervised transfer learning for detecting COVID-19 from chest X-ray (CXR) images. We compared six self-supervised learning (SSL) methods (Cross, BYOL, SimSiam, SimCLR, PIRL-jigsaw, and PIRL-rotation) with the proposed method. Additionally, we compared six pretrained DCNNs (ResNet18, ResNet50, ResNet101, CheXNet, DenseNet201, and InceptionV3) with the proposed method. We provide quantitative evaluation on the largest open COVID-19 CXR dataset and qualitative results for visual inspection. Results: Our method achieved a harmonic mean (HM) score of 0.985, AUC of 0.999, and four-class accuracy of 0.953. We also used the visualization technique Grad-CAM++ to generate visual explanations of different classes of CXR images with the proposed method to increase the interpretability. Conclusions: Our method shows that the knowledge learned from natural images using transfer learning is beneficial for SSL of the CXR images and boosts the performance of representation learning for COVID-19 detection. Our method promises to reduce the incidence of infections among radiologists and healthcare providers.
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This paper solves a generalized version of the problem of multi-source model adaptation for semantic segmentation. Model adaptation is proposed as a new domain adaptation problem which requires access to a pre-trained model instead of data for the source domain. A general multi-source setting of model adaptation assumes strictly that each source domain shares a common label space with the target domain. As a relaxation, we allow the label space of each source domain to be a subset of that of the target domain and require the union of the source-domain label spaces to be equal to the target-domain label space. For the new setting named union-set multi-source model adaptation, we propose a method with a novel learning strategy named model-invariant feature learning, which takes full advantage of the diverse characteristics of the source-domain models, thereby improving the generalization in the target domain. We conduct extensive experiments in various adaptation settings to show the superiority of our method. The code is available at https://github.com/lzy7976/union-set-model-adaptation.
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数据集复杂性评估旨在在训练分类器之前先预测具有复杂性计算的数据集上的分类性能,该分类器也可以用于分类器选择和减少数据集。深卷积神经网络(DCNN)的训练过程是迭代的且耗时的,这是由于高参数的不确定性和不同数据集引入的域移位。因此,通过在培训DCNN模型之前有效评估数据集的复杂性来预测分类性能是有意义的。本文提出了一种新的方法,称为Laplacian Spectrum(CMSAUL)下的累积最大缩放区域,该方法可以在六个数据集上实现最新的复杂性评估性能。
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背景和目标:需要分享医疗数据以实现医疗保健信息的跨机构流量并构建高准确的计算机辅助诊断系统。但是,大量的医疗数据集,保存深度卷积神经网络(DCNN)模型的大量记忆以及患者的隐私保护是可能导致医疗数据共享效率低下的问题。因此,本研究提出了一种新型的软标签数据集蒸馏方法,用于医疗数据共享。方法:所提出的方法提炼医疗图像数据的有效信息,并生成几个带有不同数据分布的压缩图像,以供匿名医疗数据共享。此外,我们的方法可以提取DCNN模型的基本权重,以减少保存训练有素的模型以进行有效的医疗数据共享所需的内存。结果:所提出的方法可以将数万张图像压缩为几个软标签图像,并将受过训练的模型的大小减少到其原始大小的几百分之一。蒸馏后获得的压缩图像已在视觉上匿名化;因此,它们不包含患者的私人信息。此外,我们可以通过少量压缩图像实现高检测性能。结论:实验结果表明,所提出的方法可以提高医疗数据共享的效率和安全性。
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