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arXiv 2104.05110stat.MEstat.CO
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网络种群的贝叶斯指数随机图模型

Bayesian exponential random graph models for populations of networks

Brieuc Lehmann, Simon White

摘要:

收集网络群体的数据正变得越来越普遍,其中每个数据点都可以被视为网络值随机变量的实现。一个典型的例子是大脑网络:一个典型的神经成像研究收集了多个个体的一个或多个大脑扫描,每个人都可以被建模为一个网络,节点对应于不同的大脑区域,边缘对应于这些区域之间的结构或功能连接。然而,大多数统计网络模型最初是为了描述一个单一的底层关系结构而提出的,尽管近年来已经看到了将这些模型扩展到网络群体的动力。在这里,我们提出了一个这样的扩展:指数随机图模型的网络人口的多级框架。通过汇集各个网络中的信息,该框架提供了一种原则性的方法来构建整个人群的关系结构。为了进行推理,我们设计了一种新的交换内吉布斯MCMC算法,产生样本的双重棘手的后验。为了说明我们的框架,我们用它来评估来自功能磁共振成像扫描的网络中的组级变化,从而推断大脑功能连接的拓扑结构中与年龄相关的差异。

英文摘要:

The collection of data on populations of networks is becoming increasingly common, where each data point can be seen as a realisation of a network-valued random variable. A canonical example is that of brain networks: a typical neuroimaging study collects one or more brain scans across multiple individuals, each of which can be modelled as a network with nodes corresponding to distinct brain regions and edges corresponding to structural or functional connections between these regions. Most statistical network models, however, were originally proposed to describe a single underlying relational structure, although recent years have seen a drive to extend these models to populations of networks. Here, we propose one such extension: a multilevel framework for populations of networks based on exponential random graph models. By pooling information across the individual networks, this framework provides a principled approach to characterise the relational structure for an entire population. To perform inference, we devise a novel exchange-within-Gibbs MCMC algorithm that generates samples from the doubly-intractable posterior. To illustrate our framework, we use it to assess group-level variations in networks derived from fMRI scans, enabling the inference of age-related differences in the topological structure of the brain's functional connectivity.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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