The COVID-19 pandemic created a deluge of questionable and contradictory scientific claims about drug efficacy -- an "infodemic" with lasting consequences for science and society. In this work, we argue that NLP models can help domain experts distill and understand the literature in this complex, high-stakes area. Our task is to automatically identify contradictory claims about COVID-19 drug efficacy. We frame this as a natural language inference problem and offer a new NLI dataset created by domain experts. The NLI framing allows us to create curricula combining existing datasets and our own. The resulting models are useful investigative tools. We provide a case study of how these models help a domain expert summarize and assess evidence concerning remdisivir and hydroxychloroquine.
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英国生物银行标准化表型代码的目的与住院的患者有关,但对于许多在门诊环境中接受治疗的患者缺失但缺失。我们描述了一种表型识别方法,该方法为所有英国生物库参与者施加了表型代码。材料和方法POPDX(基于人群的客观表型通过深度推断)是双线性机器学习框架,用于同时估计1,538个表型代码的概率。我们从英国生物库中提取了392,246个人的表型和健康相关信息,以进行POPDX开发和评估。共有12,803个ICD-10患者的诊断代码被转换为1,538个Phecodes,作为黄金标准标签。对POPDX框架进行了评估,并将其与自动多型识别的其他可用方法进行了比较。结果POPDX可以预测训练中罕见甚至未观察到的表型。我们证明了22种疾病类别的自动多型识别及其在识别与每种表型相关的关键流行病学特征方面的应用。结论POPDX有助于为下游研究提供明确定义的队列。这是一种通用方法,可以应用于具有不同但不完整数据的其他生物库。
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在三维分子结构上运行的计算方法有可能解决生物学和化学的重要问题。特别地,深度神经网络的重视,但它们在生物分子结构域中的广泛采用受到缺乏系统性能基准或统一工具包的限制,用于与分子数据相互作用。为了解决这个问题,我们呈现Atom3D,这是一个新颖的和现有的基准数据集的集合,跨越几个密钥的生物分子。我们为这些任务中的每一个实施多种三维分子学习方法,并表明它们始终如一地提高了基于单维和二维表示的方法的性能。结构的具体选择对于性能至关重要,具有涉及复杂几何形状的任务的三维卷积网络,在需要详细位置信息的系统中表现出良好的图形网络,以及最近开发的设备越多的网络显示出显着承诺。我们的结果表明,许多分子问题符合三维分子学习的增益,并且有可能改善许多仍然过分曝光的任务。为了降低进入并促进现场进一步发展的障碍,我们还提供了一套全面的DataSet处理,模型培训和在我们的开源ATOM3D Python包中的评估工具套件。所有数据集都可以从https://www.atom3d.ai下载。
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AI正在经历范式转变,随着模型的兴起(例如Bert,Dall-E,GPT-3),这些模型经过大规模的数据训练,并且可以适应广泛的下游任务。我们称这些模型基础模型来强调其至关重要但不完整的特征。该报告提供了基础模型的机会和风险的详尽说明,包括其功能(例如语言,愿景,机器人技术,推理,人类互动)和技术原则(例如,模型架构,培训程序,数据,系统,安全,安全性,评估,理论)对其应用(例如法律,医疗保健,教育)和社会影响(例如不平等,滥用,经济和环境影响,法律和道德考虑)。尽管基础模型基于标准的深度学习和转移学习,但它们的规模导致了新的新兴能力,以及它们在许多任务中的有效性都激发了同质化。同质化提供了强大的杠杆作用,但要求谨慎,因为基础模型的缺陷均由下游的所有适应模型继承。尽管即将广泛地部署基础模型,但我们目前对它们的工作方式,失败以及由于其新兴属性的影响而缺乏清晰的了解。为了解决这些问题,我们认为基础模型的许多批判性研究都需要与他们的基本社会技术性质相称。
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We study the task of learning state representations from potentially high-dimensional observations, with the goal of controlling an unknown partially observable system. We pursue a direct latent model learning approach, where a dynamic model in some latent state space is learned by predicting quantities directly related to planning (e.g., costs) without reconstructing the observations. In particular, we focus on an intuitive cost-driven state representation learning method for solving Linear Quadratic Gaussian (LQG) control, one of the most fundamental partially observable control problems. As our main results, we establish finite-sample guarantees of finding a near-optimal state representation function and a near-optimal controller using the directly learned latent model. To the best of our knowledge, despite various empirical successes, prior to this work it was unclear if such a cost-driven latent model learner enjoys finite-sample guarantees. Our work underscores the value of predicting multi-step costs, an idea that is key to our theory, and notably also an idea that is known to be empirically valuable for learning state representations.
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Three main points: 1. Data Science (DS) will be increasingly important to heliophysics; 2. Methods of heliophysics science discovery will continually evolve, requiring the use of learning technologies [e.g., machine learning (ML)] that are applied rigorously and that are capable of supporting discovery; and 3. To grow with the pace of data, technology, and workforce changes, heliophysics requires a new approach to the representation of knowledge.
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Image classification with small datasets has been an active research area in the recent past. However, as research in this scope is still in its infancy, two key ingredients are missing for ensuring reliable and truthful progress: a systematic and extensive overview of the state of the art, and a common benchmark to allow for objective comparisons between published methods. This article addresses both issues. First, we systematically organize and connect past studies to consolidate a community that is currently fragmented and scattered. Second, we propose a common benchmark that allows for an objective comparison of approaches. It consists of five datasets spanning various domains (e.g., natural images, medical imagery, satellite data) and data types (RGB, grayscale, multispectral). We use this benchmark to re-evaluate the standard cross-entropy baseline and ten existing methods published between 2017 and 2021 at renowned venues. Surprisingly, we find that thorough hyper-parameter tuning on held-out validation data results in a highly competitive baseline and highlights a stunted growth of performance over the years. Indeed, only a single specialized method dating back to 2019 clearly wins our benchmark and outperforms the baseline classifier.
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Dataset scaling, also known as normalization, is an essential preprocessing step in a machine learning pipeline. It is aimed at adjusting attributes scales in a way that they all vary within the same range. This transformation is known to improve the performance of classification models, but there are several scaling techniques to choose from, and this choice is not generally done carefully. In this paper, we execute a broad experiment comparing the impact of 5 scaling techniques on the performances of 20 classification algorithms among monolithic and ensemble models, applying them to 82 publicly available datasets with varying imbalance ratios. Results show that the choice of scaling technique matters for classification performance, and the performance difference between the best and the worst scaling technique is relevant and statistically significant in most cases. They also indicate that choosing an inadequate technique can be more detrimental to classification performance than not scaling the data at all. We also show how the performance variation of an ensemble model, considering different scaling techniques, tends to be dictated by that of its base model. Finally, we discuss the relationship between a model's sensitivity to the choice of scaling technique and its performance and provide insights into its applicability on different model deployment scenarios. Full results and source code for the experiments in this paper are available in a GitHub repository.\footnote{https://github.com/amorimlb/scaling\_matters}
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The devastation caused by the coronavirus pandemic makes it imperative to design automated techniques for a fast and accurate detection. We propose a novel non-invasive tool, using deep learning and imaging, for delineating COVID-19 infection in lungs. The Ensembling Attention-based Multi-scaled Convolution network (EAMC), employing Leave-One-Patient-Out (LOPO) training, exhibits high sensitivity and precision in outlining infected regions along with assessment of severity. The Attention module combines contextual with local information, at multiple scales, for accurate segmentation. Ensemble learning integrates heterogeneity of decision through different base classifiers. The superiority of EAMC, even with severe class imbalance, is established through comparison with existing state-of-the-art learning models over four publicly-available COVID-19 datasets. The results are suggestive of the relevance of deep learning in providing assistive intelligence to medical practitioners, when they are overburdened with patients as in pandemics. Its clinical significance lies in its unprecedented scope in providing low-cost decision-making for patients lacking specialized healthcare at remote locations.
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Objective: Imbalances of the electrolyte concentration levels in the body can lead to catastrophic consequences, but accurate and accessible measurements could improve patient outcomes. While blood tests provide accurate measurements, they are invasive and the laboratory analysis can be slow or inaccessible. In contrast, an electrocardiogram (ECG) is a widely adopted tool which is quick and simple to acquire. However, the problem of estimating continuous electrolyte concentrations directly from ECGs is not well-studied. We therefore investigate if regression methods can be used for accurate ECG-based prediction of electrolyte concentrations. Methods: We explore the use of deep neural networks (DNNs) for this task. We analyze the regression performance across four electrolytes, utilizing a novel dataset containing over 290000 ECGs. For improved understanding, we also study the full spectrum from continuous predictions to binary classification of extreme concentration levels. To enhance clinical usefulness, we finally extend to a probabilistic regression approach and evaluate different uncertainty estimates. Results: We find that the performance varies significantly between different electrolytes, which is clinically justified in the interplay of electrolytes and their manifestation in the ECG. We also compare the regression accuracy with that of traditional machine learning models, demonstrating superior performance of DNNs. Conclusion: Discretization can lead to good classification performance, but does not help solve the original problem of predicting continuous concentration levels. While probabilistic regression demonstrates potential practical usefulness, the uncertainty estimates are not particularly well-calibrated. Significance: Our study is a first step towards accurate and reliable ECG-based prediction of electrolyte concentration levels.
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