Tabular biomedical data is often high-dimensional but with a very small number of samples. Although recent work showed that well-regularised simple neural networks could outperform more sophisticated architectures on tabular data, they are still prone to overfitting on tiny datasets with many potentially irrelevant features. To combat these issues, we propose Weight Predictor Network with Feature Selection (WPFS) for learning neural networks from high-dimensional and small sample data by reducing the number of learnable parameters and simultaneously performing feature selection. In addition to the classification network, WPFS uses two small auxiliary networks that together output the weights of the first layer of the classification model. We evaluate on nine real-world biomedical datasets and demonstrate that WPFS outperforms other standard as well as more recent methods typically applied to tabular data. Furthermore, we investigate the proposed feature selection mechanism and show that it improves performance while providing useful insights into the learning task.
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Genome-wide studies leveraging recent high-throughput sequencing technologies collect high-dimensional data. However, they usually include small cohorts of patients, and the resulting tabular datasets suffer from the "curse of dimensionality". Training neural networks on such datasets is typically unstable, and the models overfit. One problem is that modern weight initialisation strategies make simplistic assumptions unsuitable for small-size datasets. We propose Graph-Conditioned MLP, a novel method to introduce priors on the parameters of an MLP. Instead of randomly initialising the first layer, we condition it directly on the training data. More specifically, we create a graph for each feature in the dataset (e.g., a gene), where each node represents a sample from the same dataset (e.g., a patient). We then use Graph Neural Networks (GNNs) to learn embeddings from these graphs and use the embeddings to initialise the MLP's parameters. Our approach opens the prospect of introducing additional biological knowledge when constructing the graphs. We present early results on 7 classification tasks from gene expression data and show that GC-MLP outperforms an MLP.
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该卷包含来自机器学习挑战的选定贡献“发现玛雅人的奥秘”,该挑战在欧洲机器学习和数据库中知识发现的欧洲挑战赛曲目(ECML PKDD 2021)中提出。遥感大大加速了古代玛雅人森林地区的传统考古景观调查。典型的探索和发现尝试,除了关注整个古老的城市外,还集中在单个建筑物和结构上。最近,已经成功地尝试了使用机器学习来识别古代玛雅人定居点。这些尝试虽然相关,但却集中在狭窄的区域上,并依靠高质量的空中激光扫描(ALS)数据,该数据仅涵盖古代玛雅人曾经定居的地区的一小部分。另一方面,由欧洲航天局(ESA)哨兵任务制作的卫星图像数据很丰富,更重要的是公开。旨在通过执行不同类型的卫星图像(Sentinel-1和Sentinel-2和ALS)的集成图像细分来定位和识别古老的Maya架构(建筑物,Aguadas和平台)的“发现和识别古代玛雅体系结构(建筑物,Aguadas和平台)的挑战的“发现和识别古老的玛雅体系结构(建筑物,阿吉达斯和平台)的“发现玛雅的奥秘”的挑战, (LIDAR)数据。
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我们提出“ AITLAS:基准竞技场” - 一个开源基准测试框架,用于评估地球观察中图像分类的最新深度学习方法(EO)。为此,我们介绍了从九种不同的最先进的体系结构得出的400多个模型的全面比较分析,并将它们与来自22个具有不同尺寸的数据集的各种多级和多标签分类任务进行比较和属性。除了完全在这些数据集上训练的模型外,我们还基于在转移学习的背景下训练的模型,利用预训练的模型变体,因为通常在实践中执行。所有提出的方法都是一般的,可以轻松地扩展到本研究中未考虑的许多其他遥感图像分类任务。为了确保可重复性并促进更好的可用性和进一步的开发,所有实验资源在内的所有实验资源,包括训练的模型,模型配置和数据集的处理详细信息(以及用于培训和评估模型的相应拆分)都在存储库上公开可用:HTTPS ://github.com/biasvariancelabs/aitlas-arena。
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基于分数的模型研究在过去几年中通过采用高斯去噪得分匹配(DSM)产生了艺术生成模型的状态。然而,高斯噪声假设具有几个高维限制,使未来甚至更高维度PDF估计的促进更具体的路线。在将理论扩展到更广泛的声音分布的情况下,我们概述了这一限制 - 即,广义正常分布。在理论上,我们可以在(去噪)得分匹配理论中放宽一个关键假设,展示了差异化的分布{几乎无处不在}允许与高斯同样的客观简化。对于噪声矢量长度分布,我们在深度学习中普遍存在的高维空间中的衡量标准的有利集中。在该过程中,我们发现偏斜噪声矢量长度分布,并开发迭代噪声缩放算法,以一致地初始化退火的Langevin动态中的多级噪声。在实践方面,我们使用重尾DSM导致分数估计,可控采样融合,更平衡的不规则的无条件生成性能,对不平衡数据集进行更高。
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基于班级成员之间不需要普遍或恒定的特征的共享特征模式,在自然世界中很常见,并且在一系列特征上都超过了一多裂的分类。我们表明,阈值元学习者(例如原型网络)需要一个嵌入维度,该维度在与任务相关的功能数量中指数呈指数级,以模拟这些功能。相比之下,默认情况下,注意分类器(例如匹配网络)是多真的,并且能够通过线性嵌入维度解决这些问题。但是,我们发现,在存在任务核定特征的情况下,元学习问题固有的特征,注意模型容易受到错误分类的影响。为了应对这一挑战,我们提出了一种自我注意的特征选择机制,该机制可适应非歧视性特征。我们证明了我们的方法在元学习布尔功能以及合成和现实世界中的几个学习任务中的有效性。
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Text classifiers have promising applications in high-stake tasks such as resume screening and content moderation. These classifiers must be fair and avoid discriminatory decisions by being invariant to perturbations of sensitive attributes such as gender or ethnicity. However, there is a gap between human intuition about these perturbations and the formal similarity specifications capturing them. While existing research has started to address this gap, current methods are based on hardcoded word replacements, resulting in specifications with limited expressivity or ones that fail to fully align with human intuition (e.g., in cases of asymmetric counterfactuals). This work proposes novel methods for bridging this gap by discovering expressive and intuitive individual fairness specifications. We show how to leverage unsupervised style transfer and GPT-3's zero-shot capabilities to automatically generate expressive candidate pairs of semantically similar sentences that differ along sensitive attributes. We then validate the generated pairs via an extensive crowdsourcing study, which confirms that a lot of these pairs align with human intuition about fairness in the context of toxicity classification. Finally, we show how limited amounts of human feedback can be leveraged to learn a similarity specification that can be used to train downstream fairness-aware models.
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Accurate speed estimation of road vehicles is important for several reasons. One is speed limit enforcement, which represents a crucial tool in decreasing traffic accidents and fatalities. Compared with other research areas and domains, the number of available datasets for vehicle speed estimation is still very limited. We present a dataset of on-road audio-video recordings of single vehicles passing by a camera at known speeds, maintained stable by the on-board cruise control. The dataset contains thirteen vehicles, selected to be as diverse as possible in terms of manufacturer, production year, engine type, power and transmission, resulting in a total of $ 400 $ annotated audio-video recordings. The dataset is fully available and intended as a public benchmark to facilitate research in audio-video vehicle speed estimation. In addition to the dataset, we propose a cross-validation strategy which can be used in a machine learning model for vehicle speed estimation. Two approaches to training-validation split of the dataset are proposed.
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Novel view synthesis and 3D modeling using implicit neural field representation are shown to be very effective for calibrated multi-view cameras. Such representations are known to benefit from additional geometric and semantic supervision. Most existing methods that exploit additional supervision require dense pixel-wise labels or localized scene priors. These methods cannot benefit from high-level vague scene priors provided in terms of scenes' descriptions. In this work, we aim to leverage the geometric prior of Manhattan scenes to improve the implicit neural radiance field representations. More precisely, we assume that only the knowledge of the scene (under investigation) being Manhattan is known - with no additional information whatsoever - with an unknown Manhattan coordinate frame. Such high-level prior is then used to self-supervise the surface normals derived explicitly in the implicit neural fields. Our modeling allows us to group the derived normals, followed by exploiting their orthogonality constraints for self-supervision. Our exhaustive experiments on datasets of diverse indoor scenes demonstrate the significant benefit of the proposed method over the established baselines.
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在我们不断变化的气候中,使用模型来评估天气和气候对社会和企业的后续后果的风险及其后续后果至关重要。这种模型的操作在历史上是定制的,并限制在特定的计算基础架构,驱动数据集和预定义的配置上。这些约束通过缩放模型运行并将模型掌握在感兴趣的用户手中。在这里,我们提出了一个基于云的模块化框架,用于部署和操作地理空间模型,最初应用于气候影响。气候冲击建模框架(CIMF)可以以动态和灵活的方式部署模块化工作流程。用户可以以简化的方式指定工作流程组件,然后可以轻松地将这些组件组织成不同的配置,以以不同的方式和不同的尺度评估风险。这还可以使不同的模型(物理模拟或机器学习模型)和工作流程连接以产生合并的风险评估。洪水建模被用作端到端的示例,以证明CIMF的操作。
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