通过图形结构表示数据标识在多个数据分析应用中提取信息的最有效方法之一。当调查多模式数据集时,这尤其如此,因为通过各种传感策略收集的记录被考虑并探索。然而,经典曲线图信号处理基于根据热扩散机构配置的信息传播的模型。该系统提供了对多模式数据分析不适用于多模式数据分析的数据属性的若干约束和假设,特别是当考虑从异构源收集的大规模数据集,因此结果的准确性和稳健性可能会受到严重危害。在本文中,我们介绍了一种基于流体扩散的图表定义模型。该方法提高了基于图形的数据分析的能力,以考虑运行方案中现代数据分析的几个问题,从而为对考试记录的记录底层的现象提供了一种精确,多才多艺的,有效地理解平台,以及完全利用记录的多样性提供的潜力,以获得数据的彻底表征及其意义。在这项工作中,我们专注于使用这种流体扩散模型来驱动社区检测方案,即根据节点中的节点中的相似性将多模式数据集分为多个组中。在不同应用场景中测试真正的多模式数据集实现的实验结果表明,我们的方法能够强烈优先于多媒体数据分析中的社区检测的最先进方案。
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最近有一项激烈的活动在嵌入非常高维和非线性数据结构的嵌入中,其中大部分在数据科学和机器学习文献中。我们分四部分调查这项活动。在第一部分中,我们涵盖了非线性方法,例如主曲线,多维缩放,局部线性方法,ISOMAP,基于图形的方法和扩散映射,基于内核的方法和随机投影。第二部分与拓扑嵌入方法有关,特别是将拓扑特性映射到持久图和映射器算法中。具有巨大增长的另一种类型的数据集是非常高维网络数据。第三部分中考虑的任务是如何将此类数据嵌入中等维度的向量空间中,以使数据适合传统技术,例如群集和分类技术。可以说,这是算法机器学习方法与统计建模(所谓的随机块建模)之间的对比度。在论文中,我们讨论了两种方法的利弊。调查的最后一部分涉及嵌入$ \ mathbb {r}^ 2 $,即可视化中。提出了三种方法:基于第一部分,第二和第三部分中的方法,$ t $ -sne,UMAP和大节。在两个模拟数据集上进行了说明和比较。一个由嘈杂的ranunculoid曲线组成的三胞胎,另一个由随机块模型和两种类型的节点产生的复杂性的网络组成。
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Research in Graph Signal Processing (GSP) aims to develop tools for processing data defined on irregular graph domains. In this paper we first provide an overview of core ideas in GSP and their connection to conventional digital signal processing, along with a brief historical perspective to highlight how concepts recently developed in GSP build on top of prior research in other areas. We then summarize recent advances in developing basic GSP tools, including methods for sampling, filtering or graph learning. Next, we review progress in several application areas using GSP, including processing and analysis of sensor network data, biological data, and applications to image processing and machine learning.
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We review clustering as an analysis tool and the underlying concepts from an introductory perspective. What is clustering and how can clusterings be realised programmatically? How can data be represented and prepared for a clustering task? And how can clustering results be validated? Connectivity-based versus prototype-based approaches are reflected in the context of several popular methods: single-linkage, spectral embedding, k-means, and Gaussian mixtures are discussed as well as the density-based protocols (H)DBSCAN, Jarvis-Patrick, CommonNN, and density-peaks.
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随机块模型(SBM)是一个随机图模型,其连接不同的顶点组不同。它被广泛用作研究聚类和社区检测的规范模型,并提供了肥沃的基础来研究组合统计和更普遍的数据科学中出现的信息理论和计算权衡。该专着调查了最近在SBM中建立社区检测的基本限制的最新发展,无论是在信息理论和计算方案方面,以及各种恢复要求,例如精确,部分和弱恢复。讨论的主要结果是在Chernoff-Hellinger阈值中进行精确恢复的相转换,Kesten-Stigum阈值弱恢复的相变,最佳的SNR - 单位信息折衷的部分恢复以及信息理论和信息理论之间的差距计算阈值。该专着给出了在寻求限制时开发的主要算法的原则推导,特别是通过绘制绘制,半定义编程,(线性化)信念传播,经典/非背带频谱和图形供电。还讨论了其他块模型的扩展,例如几何模型和一些开放问题。
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Experimental sciences have come to depend heavily on our ability to organize, interpret and analyze high-dimensional datasets produced from observations of a large number of variables governed by natural processes. Natural laws, conservation principles, and dynamical structure introduce intricate inter-dependencies among these observed variables, which in turn yield geometric structure, with fewer degrees of freedom, on the dataset. We show how fine-scale features of this structure in data can be extracted from \emph{discrete} approximations to quantum mechanical processes given by data-driven graph Laplacians and localized wavepackets. This data-driven quantization procedure leads to a novel, yet natural uncertainty principle for data analysis induced by limited data. We illustrate the new approach with algorithms and several applications to real-world data, including the learning of patterns and anomalies in social distancing and mobility behavior during the COVID-19 pandemic.
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马尔可夫链是一类概率模型,在定量科学中已广泛应用。这部分是由于它们的多功能性,但是可以通过分析探测的便利性使其更加复杂。本教程为马尔可夫连锁店提供了深入的介绍,并探索了它们与图形和随机步行的联系。我们利用从线性代数和图形论的工具来描述不同类型的马尔可夫链的过渡矩阵,特别着眼于探索与这些矩阵相对应的特征值和特征向量的属性。提出的结果与机器学习和数据挖掘中的许多方法有关,我们在各个阶段描述了这些方法。本文并没有本身就成为一项新颖的学术研究,而是提出了一些已知结果的集合以及一些新概念。此外,该教程的重点是向读者提供直觉,而不是正式的理解,并且仅假定对线性代数和概率理论的概念的基本曝光。因此,来自各种学科的学生和研究人员可以访问它。
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Selecting subsets of features that differentiate between two conditions is a key task in a broad range of scientific domains. In many applications, the features of interest form clusters with similar effects on the data at hand. To recover such clusters we develop DiSC, a data-driven approach for detecting groups of features that differentiate between conditions. For each condition, we construct a graph whose nodes correspond to the features and whose weights are functions of the similarity between them for that condition. We then apply a spectral approach to compute subsets of nodes whose connectivity differs significantly between the condition-specific feature graphs. On the theoretical front, we analyze our approach with a toy example based on the stochastic block model. We evaluate DiSC on a variety of datasets, including MNIST, hyperspectral imaging, simulated scRNA-seq and task fMRI, and demonstrate that DiSC uncovers features that better differentiate between conditions compared to competing methods.
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Many scientific fields study data with an underlying structure that is a non-Euclidean space. Some examples include social networks in computational social sciences, sensor networks in communications, functional networks in brain imaging, regulatory networks in genetics, and meshed surfaces in computer graphics. In many applications, such geometric data are large and complex (in the case of social networks, on the scale of billions), and are natural targets for machine learning techniques. In particular, we would like to use deep neural networks, which have recently proven to be powerful tools for a broad range of problems from computer vision, natural language processing, and audio analysis. However, these tools have been most successful on data with an underlying Euclidean or grid-like structure, and in cases where the invariances of these structures are built into networks used to model them.Geometric deep learning is an umbrella term for emerging techniques attempting to generalize (structured) deep neural models to non-Euclidean domains such as graphs and manifolds. The purpose of this paper is to overview different examples of geometric deep learning problems and present available solutions, key difficulties, applications, and future research directions in this nascent field.
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The stochastic block model (SBM) is a random graph model with planted clusters. It is widely employed as a canonical model to study clustering and community detection, and provides generally a fertile ground to study the statistical and computational tradeoffs that arise in network and data sciences.This note surveys the recent developments that establish the fundamental limits for community detection in the SBM, both with respect to information-theoretic and computational thresholds, and for various recovery requirements such as exact, partial and weak recovery (a.k.a., detection). The main results discussed are the phase transitions for exact recovery at the Chernoff-Hellinger threshold, the phase transition for weak recovery at the Kesten-Stigum threshold, the optimal distortion-SNR tradeoff for partial recovery, the learning of the SBM parameters and the gap between information-theoretic and computational thresholds.The note also covers some of the algorithms developed in the quest of achieving the limits, in particular two-round algorithms via graph-splitting, semi-definite programming, linearized belief propagation, classical and nonbacktracking spectral methods. A few open problems are also discussed.
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Pre-publication draft of a book to be published byMorgan & Claypool publishers. Unedited version released with permission. All relevant copyrights held by the author and publisher extend to this pre-publication draft.
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在本文中,我们提出了一种新方法来检测具有归因顶点的无向图中的簇。目的是将不仅在结构连接性方面,而且在属性值方面相似的顶点分组。我们通过创建[6,38]中提出的其他顶点和边缘,将顶点之间的结构和属性相似。然后将增强图嵌入到与其拉普拉斯式相关的欧几里得空间中,在该空间中,应用了修改的K-均值算法以识别簇。修改后的k均值依赖于矢量距离度量,根据每个原始顶点,我们分配了合适的矢量值坐标集,这取决于结构连接性和属性相似性,因此每个原始图顶点都被认为是$ M+1的代表增强图的$顶点,如果$ m $是顶点属性的数量。为了定义坐标矢量,我们基于自适应AMG(代数多机)方法采用了我们最近提出的算法,该方法识别了嵌入欧几里得空间中的坐标方向,以代数平滑的矢量相对于我们的增强图Laplacian,从而扩展了laplacian,从而扩展了坐标。没有属性的图形的先前结果。我们通过与一些知名方法进行比较,分析了我们提出的聚类方法的有效性,这些方法可以免费获得软件实现,并与文献中报告的结果相比,在两种不同类型的广泛使用的合成图上以及在某些现实世界中的图形上。
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Graph clustering is a fundamental problem in unsupervised learning, with numerous applications in computer science and in analysing real-world data. In many real-world applications, we find that the clusters have a significant high-level structure. This is often overlooked in the design and analysis of graph clustering algorithms which make strong simplifying assumptions about the structure of the graph. This thesis addresses the natural question of whether the structure of clusters can be learned efficiently and describes four new algorithmic results for learning such structure in graphs and hypergraphs. All of the presented theoretical results are extensively evaluated on both synthetic and real-word datasets of different domains, including image classification and segmentation, migration networks, co-authorship networks, and natural language processing. These experimental results demonstrate that the newly developed algorithms are practical, effective, and immediately applicable for learning the structure of clusters in real-world data.
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学习涉及时变和不断发展的系统动态的控制政策通常对主流强化学习算法构成了巨大的挑战。在大多数标准方法中,通常认为动作是一组刚性的,固定的选择,这些选择以预定义的方式顺序应用于状态空间。因此,在不诉诸于重大学习过程的情况下,学识渊博的政策缺乏适应动作集和动作的“行为”结果的能力。此外,标准行动表示和动作引起的状态过渡机制固有地限制了如何将强化学习应用于复杂的现实世界应用中,这主要是由于所得大的状态空间的棘手性以及缺乏概括的学术知识对国家空间未知部分的政策。本文提出了一个贝叶斯味的广义增强学习框架,首先建立参数动作模型的概念,以更好地应对不确定性和流体动作行为,然后将增强领域的概念作为物理启发的结构引入通过“极化体验颗粒颗粒建立) “维持在学习代理的工作记忆中。这些粒子有效地编码了以自组织方式随时间演变的动态学习体验。在强化领域之上,我们将进一步概括策略学习过程,以通过将过去的记忆视为具有隐式图结构来结合高级决策概念,在该结构中,过去的内存实例(或粒子)与决策之间的相似性相互联系。定义,因此,可以应用“关联记忆”原则来增强学习代理的世界模型。
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In recent years, spectral clustering has become one of the most popular modern clustering algorithms. It is simple to implement, can be solved efficiently by standard linear algebra software, and very often outperforms traditional clustering algorithms such as the k-means algorithm. On the first glance spectral clustering appears slightly mysterious, and it is not obvious to see why it works at all and what it really does. The goal of this tutorial is to give some intuition on those questions. We describe different graph Laplacians and their basic properties, present the most common spectral clustering algorithms, and derive those algorithms from scratch by several different approaches. Advantages and disadvantages of the different spectral clustering algorithms are discussed.
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信号处理是几乎任何传感器系统的基本组件,具有不同科学学科的广泛应用。时间序列数据,图像和视频序列包括可以增强和分析信息提取和量化的代表性形式的信号。人工智能和机器学习的最近进步正在转向智能,数据驱动,信号处理的研究。该路线图呈现了最先进的方法和应用程序的关键概述,旨在突出未来的挑战和对下一代测量系统的研究机会。它涵盖了广泛的主题,从基础到工业研究,以简明的主题部分组织,反映了每个研究领域的当前和未来发展的趋势和影响。此外,它为研究人员和资助机构提供了识别新前景的指导。
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社区检测是网络科学中最重要的方法领域之一,在过去的几十年里引起了大量关注的方法之一。该区域处理网络的自动部门到基础构建块中,目的是提供其大规模结构的概要。尽管它的重要性和广泛的采用普及,所谓的最先进和实际在各种领域实际使用的方法之间存在明显的差距。在这里,我们试图通过根据是否具有“描述性”或“推论”目标来划分现有方法来解决这种差异。虽然描述性方法在基于社区结构的直观概念的网络中找到模式的模式,但是推理方法阐述了精确的生成模型,并尝试将其符合数据。通过这种方式,他们能够为网络形成机制提供见解,并以统计证据支持的方式与随机性的单独结构。我们审查如何使用推论目标采用描述性方法被陷入困境和误导性答案,因此应该一般而言。我们认为推理方法更通常与更清晰的科学问题一致,产生更强大的结果,并且应该是一般的首选。我们试图消除一些神话和半真半假在实践中使用社区检测时,努力改善这些方法的使用以及对结果的解释。
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我们介绍了一种算法,用于计算采样歧管的测量测量算法,其依赖于对采样数据的植物嵌入的曲线图的模拟。我们的方法利用经典的结果在半导体分析和量子古典对应中,并形成用于学习数据集的歧管的技术的基础,随后用于高维数据集的非线性维度降低。我们以基于CoVID-19移动数据的聚类演示,从模型歧管中采样数据采样的数据,并通过集群演示来说明新的算法。最后,我们的方法揭示了数据采样和量化提供的离散化之间有趣的连接。
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许多复杂网络的结构包括其拓扑顶部的边缘方向性和权重。可以无缝考虑这些属性组合的网络分析是可取的。在本文中,我们研究了两个重要的这样的网络分析技术,即中心和聚类。采用信息流基于集群的模型,该模型本身就是在计算中心的信息定理措施时构建。我们的主要捐款包括马尔可夫熵中心的广义模型,灵活地调整节点度,边缘权重和方向的重要性,具有闭合形式的渐近分析。它导致一种新颖的两级图形聚类算法。中心分析有助于推理我们对给定图形的方法的适用性,并确定探索当地社区结构的“查询”节点,从而导致群集聚类机制。熵中心计算由我们的聚类算法摊销,使其计算得高效:与使用马尔可夫熵中心为聚类的先前方法相比,我们的实验表明了多个速度的速度。我们的聚类算法自然地继承了适应边缘方向性的灵活性,以及​​边缘权重和节点度之间的不同解释和相互作用。总的来说,本文不仅具有显着的理论和概念贡献,还转化为实际相关性的文物,产生新的,有效和可扩展的中心计算和图形聚类算法,其有效通过广泛的基准测试进行了验证。
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In applications such as social, energy, transportation, sensor, and neuronal networks, high-dimensional data naturally reside on the vertices of weighted graphs. The emerging field of signal processing on graphs merges algebraic and spectral graph theoretic concepts with computational harmonic analysis to process such signals on graphs. In this tutorial overview, we outline the main challenges of the area, discuss different ways to define graph spectral domains, which are the analogues to the classical frequency domain, and highlight the importance of incorporating the irregular structures of graph data domains when processing signals on graphs. We then review methods to generalize fundamental operations such as filtering, translation, modulation, dilation, and downsampling to the graph setting, and survey the localized, multiscale transforms that have been proposed to efficiently extract information from high-dimensional data on graphs. We conclude with a brief discussion of open issues and possible extensions.
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