arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2002.08521stat.MEmath.STstat.TH
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群体网络霍克斯过程

Group Network Hawkes Process

Guanhua Fang, Ganggang Xu, Haochen Xu, Xuening Zhu, Yongtao Guan

AI总结:

本文提出群体网络霍克斯过程(GNHP)模型,通过潜在群体结构刻画网络个体动态交互,结合最大似然与快速EM算法聚类并估计参数,理论性质与实证验证了其有效性。

摘要:

在本工作中,我们研究了在网络中互动的个体的事件发生情况。为了刻画个体之间的动态交互,我们提出了一种群体网络霍克斯过程(GNHP)模型,其网络结构是可观测且固定的。特别地,我们在个体中引入了一个潜在的群体结构,以解释异质性的用户特定特征。提出了一种最大似然方法,用于同时聚类网络中的个体并估计模型参数。随后,利用所提出的GNHP模型的分支表示,开发了一种快速的EM算法。在潜在群体数量$G$被过度设定或正确设定的两种情况下,研究了群体成员和模型参数所得估计量的理论性质。推导了一种数据驱动的准则,该准则在温和条件下能够一致地识别真实的$G$。大量的仿真研究以及对中国新浪微博收集的数据集的应用,用以说明所提出方法的有效性。

英文摘要:

In this work, we study the event occurrences of individuals interacting in a network. To characterize the dynamic interactions among the individuals, we propose a group network Hawkes process (GNHP) model whose network structure is observed and fixed. In particular, we introduce a latent group structure among individuals to account for the heterogeneous user-specific characteristics. A maximum likelihood approach is proposed to simultaneously cluster individuals in the network and estimate model parameters. A fast EM algorithm is subsequently developed by utilizing the branching representation of the proposed GNHP model. Theoretical properties of the resulting estimators of group memberships and model parameters are investigated under both settings when the number of latent groups $G$ is over-specified or correctly specified. A data-driven criterion that can consistently identify the true $G$ under mild conditions is derived. Extensive simulation studies and an application to a data set collected from Sina Weibo are used to illustrate the effectiveness of the proposed methodology.

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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