Wasserstein的分布在强大的优化方面已成为强大估计的有力框架,享受良好的样本外部性能保证,良好的正则化效果以及计算上可易处理的双重重新纠正。在这样的框架中,通过将最接近经验分布的所有概率分布中最接近的所有概率分布中最小化的最差预期损失来最大程度地减少估计量。在本文中,我们提出了一个在噪声线性测量中估算未知参数的Wasserstein分布稳定的M估计框架,我们专注于分析此类估计器的平方误差性能的重要且具有挑战性的任务。我们的研究是在现代的高维比例状态下进行的,在该状态下,环境维度和样品数量都以相对的速度进行编码,该速率以编码问题的下/过度参数化的比例。在各向同性高斯特征假设下,我们表明可以恢复平方误差作为凸 - 串联优化问题的解,令人惊讶的是,它在最多四个标量变量中都涉及。据我们所知,这是在Wasserstein分布强劲的M估计背景下研究此问题的第一项工作。
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脑转移经常发生在转移性癌症的患者中。早期和准确地检测脑转移对于放射治疗的治疗计划和预后至关重要。为了提高深入学习的脑转移检测性能,提出了一种称为体积级灵敏度特异性(VSS)的定制检测损失,该损失是单个转移检测灵敏度和(子)体积水平的特异性。作为敏感性和精度始终在转移水平中始终是折射率,可以通过调节VSS损耗中的重量而无需骰子分数系数进行分段转移来实现高精度或高精度。为了减少被检测为假阳性转移的转移样结构,提出了一种时间的现有量作为神经网络的额外输入。我们提出的VSS损失提高了脑转移检测的敏感性,将灵敏度提高了86.7%至95.5%。或者,它将精度提高了68.8%至97.8%。随着额外的时间现有量,在高灵敏度模型中,约45%的假阳性转移减少,高特异性模型的精度达到99.6%。所有转移的平均骰子系数约为0.81。随着高灵敏度和高特异性模型的集合,平均每位患者的1.5个假阳性转移需要进一步检查,而大多数真正的阳性转移确认。该集合学习能够区分从需要特殊专家审查或进一步跟进的转移候选人的高信心真正的阳性转移,特别适合实际临床实践中专家支持的要求。
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现代应用要求机器人符合多个通常相互冲突的规则,并与其他代理商互动。我们将Posetal Games作为一类游戏,每个玩家通过部分有序的一组指标表达了对结果的偏好。这允许人们将每个玩家的分层优先级与环境的交互性质组合。通过语境化标准游戏理论概念,我们为参与者的偏好提供了两个足够的条件,以便在有限作用集中证明纯NASH均衡的存在。此外,我们在偏好结构上定义正式操作,并将其链接到游戏解决方案的细化,显示如何系统地缩小均衡集合。所提出的结果展示在驾驶游戏中,自主车辆从有限组轨迹中选择。结果证明了对每个玩家最小禁区的结果的可解释性。
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学习如何随着时间的推移发展复杂的动态系统是系统识别中的关键挑战。对于安全关键系统,它通常是至关重要的,因为学习的模型保证会聚到一些均衡点。为此,当完全观察到各种时,用神经拉布诺夫函数规范的神经杂物是一种有希望的方法。然而,对于实际应用,部分观察是常态。正如我们将证明,未观察到的增强状态的初始化可能成为神经杂物余下的关键问题。为了减轻这个问题,我们建议增加该系统的历史历史。通过国家增强在离散时间系统中的启发,我们得到了神经延迟微分方程。基于古典时间延迟稳定性分析,我们展示了如何确保学习模型的稳定性,从理论上分析我们的方法。我们的实验表明其适用于稳定的系统识别部分观察到的系统和学习延迟反馈控制中的稳定反馈策略。
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越来越多的间歇可再生能源的整合,特别是在分配水平,需要对TheGrid的知识而设计的先进规划和优化方法,特别是捕获电网拓扑和线参数的进入矩阵。然而,对进入矩阵的可靠估计可以丢失或迅速地过时用于时间变化网格。在这项工作中,我们提出了利用从微量PMU收集的电压和电流测量的数据驱动的识别方法。更确切地说,我们首先呈现最大的似然方法,然后朝着贝叶斯框架移动,利用最大后验估计的原则。与大多数现有的Con-Tribution相比,我们的方法不仅是电压和电流数据上的测量噪声中的因素,而且还能够利用可用的先验信息,例如稀疏性模式和已知的列表参数。在基准案件上进行的模拟表明,与储藏仪相比,我们的方法可以实现明显更大的准确性。
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Machine learning models are typically evaluated by computing similarity with reference annotations and trained by maximizing similarity with such. Especially in the bio-medical domain, annotations are subjective and suffer from low inter- and intra-rater reliability. Since annotations only reflect the annotation entity's interpretation of the real world, this can lead to sub-optimal predictions even though the model achieves high similarity scores. Here, the theoretical concept of Peak Ground Truth (PGT) is introduced. PGT marks the point beyond which an increase in similarity with the reference annotation stops translating to better Real World Model Performance (RWMP). Additionally, a quantitative technique to approximate PGT by computing inter- and intra-rater reliability is proposed. Finally, three categories of PGT-aware strategies to evaluate and improve model performance are reviewed.
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Mixtures of von Mises-Fisher distributions can be used to cluster data on the unit hypersphere. This is particularly adapted for high-dimensional directional data such as texts. We propose in this article to estimate a von Mises mixture using a l 1 penalized likelihood. This leads to sparse prototypes that improve clustering interpretability. We introduce an expectation-maximisation (EM) algorithm for this estimation and explore the trade-off between the sparsity term and the likelihood one with a path following algorithm. The model's behaviour is studied on simulated data and, we show the advantages of the approach on real data benchmark. We also introduce a new data set on financial reports and exhibit the benefits of our method for exploratory analysis.
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Passive monitoring of acoustic or radio sources has important applications in modern convenience, public safety, and surveillance. A key task in passive monitoring is multiobject tracking (MOT). This paper presents a Bayesian method for multisensor MOT for challenging tracking problems where the object states are high-dimensional, and the measurements follow a nonlinear model. Our method is developed in the framework of factor graphs and the sum-product algorithm (SPA). The multimodal probability density functions (pdfs) provided by the SPA are effectively represented by a Gaussian mixture model (GMM). To perform the operations of the SPA in high-dimensional spaces, we make use of Particle flow (PFL). Here, particles are migrated towards regions of high likelihood based on the solution of a partial differential equation. This makes it possible to obtain good object detection and tracking performance even in challenging multisensor MOT scenarios with single sensor measurements that have a lower dimension than the object positions. We perform a numerical evaluation in a passive acoustic monitoring scenario where multiple sources are tracked in 3-D from 1-D time-difference-of-arrival (TDOA) measurements provided by pairs of hydrophones. Our numerical results demonstrate favorable detection and estimation accuracy compared to state-of-the-art reference techniques.
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Location-aware networks will introduce new services and applications for modern convenience, surveillance, and public safety. In this paper, we consider the problem of cooperative localization in a wireless network where the position of certain anchor nodes can be controlled. We introduce an active planning method that aims at moving the anchors such that the information gain of future measurements is maximized. In the control layer of the proposed method, control inputs are calculated by minimizing the traces of approximate inverse Bayesian Fisher information matrixes (FIMs). The estimation layer computes estimates of the agent states and provides Gaussian representations of marginal posteriors of agent positions to the control layer for approximate Bayesian FIM computations. Based on a cost function that accumulates Bayesian FIM contributions over a sliding window of discrete future timesteps, a receding horizon (RH) control is performed. Approximations that make it possible to solve the resulting tree-search problem efficiently are also discussed. A numerical case study demonstrates the intelligent behavior of a single controlled anchor in a 3-D scenario and the resulting significantly improved localization accuracy.
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This paper presents an introduction to the state-of-the-art in anomaly and change-point detection. On the one hand, the main concepts needed to understand the vast scientific literature on those subjects are introduced. On the other, a selection of important surveys and books, as well as two selected active research topics in the field, are presented.
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