Mechanistic cardiac electrophysiology models allow for personalized simulations of the electrical activity in the heart and the ensuing electrocardiogram (ECG) on the body surface. As such, synthetic signals possess known ground truth labels of the underlying disease and can be employed for validation of machine learning ECG analysis tools in addition to clinical signals. Recently, synthetic ECGs were used to enrich sparse clinical data or even replace them completely during training leading to improved performance on real-world clinical test data. We thus generated a novel synthetic database comprising a total of 16,900 12 lead ECGs based on electrophysiological simulations equally distributed into healthy control and 7 pathology classes. The pathological case of myocardial infraction had 6 sub-classes. A comparison of extracted features between the virtual cohort and a publicly available clinical ECG database demonstrated that the synthetic signals represent clinical ECGs for healthy and pathological subpopulations with high fidelity. The ECG database is split into training, validation, and test folds for development and objective assessment of novel machine learning algorithms.
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我们提出了Fibernet,一种估计\ emph {in-Vivo}的方法,从电动激活的多个导管记录中,人心房的心脏纤维结构。心脏纤维在心脏的电力功能中起着核心作用,但是它们很难确定体内,因此在现有心脏模型中很少有特定于患者的特定于患者。 Fibernet通过解决物理知识的神经网络的逆问题来学习纤维布置。逆问题等于从一组稀疏激活图中识别心脏传播模型的传导速度张量。多个地图的使用可以同时识别传导速度张量(包括局部纤维角)的所有组件。我们对合成2-D和3-D示例,扩散张量纤维和患者特异性病例进行广泛测试。我们表明,在存在噪声的情况下,也足以准确捕获纤维。随着地图的较少,正则化的作用变得突出。此外,我们表明拟合的模型可以稳健地重现看不见的激活图。我们设想,纤维网将帮助创建特定于患者的个性化医学模型。完整代码可在http://github.com/fsahli/fibernet上找到。
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心脏电生理学领域试图摘要,描述并最终模拟心跳的电气特性。随着近期心脏电生理学的进展,模型与以往更强大和描述。然而,为了前进到逆电生理学建模领域,即从诸如ECG的电测量中创建模型,较少调查的模拟ECGS的平滑度W.R.T.需要进一步探索模型参数。本文在整个管道方面讨论了描述了描述生理参数的方式,我们到达模拟的心电图。采用这种管道,我们创建了一种简化理想化的左心室模型的测试台,并通过平滑成本函数来证明高效逆建模的最重要因素。这些知识对于在未来的优化和机器学习方法中设计和创建逆模型非常重要。
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Human Activity Recognition (HAR) using on-body devices identifies specific human actions in unconstrained environments. HAR is challenging due to the inter and intra-variance of human movements; moreover, annotated datasets from on-body devices are scarce. This problem is mainly due to the difficulty of data creation, i.e., recording, expensive annotation, and lack of standard definitions of human activities. Previous works demonstrated that transfer learning is a good strategy for addressing scenarios with scarce data. However, the scarcity of annotated on-body device datasets remains. This paper proposes using datasets intended for human-pose estimation as a source for transfer learning; specifically, it deploys sequences of annotated pixel coordinates of human joints from video datasets for HAR and human pose estimation. We pre-train a deep architecture on four benchmark video-based source datasets. Finally, an evaluation is carried out on three on-body device datasets improving HAR performance.
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This paper presents a Neuromorphic Starter Kit, which has been designed to help a variety of research groups perform research, exploration and real-world demonstrations of brain-based, neuromorphic processors and hardware environments. A prototype kit has been built and tested. We explain the motivation behind the kit, its design and composition, and a prototype physical demonstration.
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Human variation in labeling is often considered noise. Annotation projects for machine learning (ML) aim at minimizing human label variation, with the assumption to maximize data quality and in turn optimize and maximize machine learning metrics. However, this conventional practice assumes that there exists a ground truth, and neglects that there exists genuine human variation in labeling due to disagreement, subjectivity in annotation or multiple plausible answers. In this position paper, we argue that this big open problem of human label variation persists and critically needs more attention to move our field forward. This is because human label variation impacts all stages of the ML pipeline: data, modeling and evaluation. However, few works consider all of these dimensions jointly; and existing research is fragmented. We reconcile different previously proposed notions of human label variation, provide a repository of publicly-available datasets with un-aggregated labels, depict approaches proposed so far, identify gaps and suggest ways forward. As datasets are becoming increasingly available, we hope that this synthesized view on the 'problem' will lead to an open discussion on possible strategies to devise fundamentally new directions.
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Calibration is a popular framework to evaluate whether a classifier knows when it does not know - i.e., its predictive probabilities are a good indication of how likely a prediction is to be correct. Correctness is commonly estimated against the human majority class. Recently, calibration to human majority has been measured on tasks where humans inherently disagree about which class applies. We show that measuring calibration to human majority given inherent disagreements is theoretically problematic, demonstrate this empirically on the ChaosNLI dataset, and derive several instance-level measures of calibration that capture key statistical properties of human judgements - class frequency, ranking and entropy.
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Dysgraphia, a handwriting learning disability, has a serious negative impact on children's academic results, daily life and overall wellbeing. Early detection of dysgraphia allows for an early start of a targeted intervention. Several studies have investigated dysgraphia detection by machine learning algorithms using a digital tablet. However, these studies deployed classical machine learning algorithms with manual feature extraction and selection as well as binary classification: either dysgraphia or no dysgraphia. In this work, we investigated fine grading of handwriting capabilities by predicting SEMS score (between 0 and 12) with deep learning. Our approach provide accuracy more than 99% and root mean square error lower than one, with automatic instead of manual feature extraction and selection. Furthermore, we used smart pen called SensoGrip, a pen equipped with sensors to capture handwriting dynamics, instead of a tablet, enabling writing evaluation in more realistic scenarios.
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媒体报道对公众对事件的看法具有重大影响。尽管如此,媒体媒体经常有偏见。偏见新闻文章的一种方法是改变选择一词。通过单词选择对偏见的自动识别是具有挑战性的,这主要是由于缺乏黄金标准数据集和高环境依赖性。本文介绍了Babe,这是由训练有素的专家创建的强大而多样化的数据集,用于媒体偏见研究。我们还分析了为什么专家标签在该域中至关重要。与现有工作相比,我们的数据集提供了更好的注释质量和更高的通知者协议。它由主题和插座之间平衡的3,700个句子组成,其中包含单词和句子级别上的媒体偏见标签。基于我们的数据,我们还引入了一种自动检测新闻文章中偏见的句子的方法。我们最佳性能基于BERT的模型是在由遥远标签组成的较大语料库中进行预训练的。对我们提出的监督数据集进行微调和评估模型,我们达到了0.804的宏F1得分,表现优于现有方法。
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适当的评估和实验设计对于经验科学是基础,尤其是在数据驱动领域。例如,由于语言的计算建模成功,研究成果对最终用户产生了越来越直接的影响。随着最终用户采用差距的减少,需求增加了,以确保研究社区和从业者开发的工具和模型可靠,可信赖,并且支持用户的目标。在该立场论文中,我们专注于评估视觉文本分析方法的问题。我们从可视化和自然语言处理社区中采用跨学科的角度,因为我们认为,视觉文本分析的设计和验证包括超越计算或视觉/交互方法的问题。我们确定了四个关键的挑战群,用于评估视觉文本分析方法(数据歧义,实验设计,用户信任和“大局”问题),并从跨学科的角度为研究机会提供建议。
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