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Mixed-Effect Time-Varying Network Model and Application in Brain Connectivity Analysis

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 نشر من قبل Emma Jingfei Zhang
 تاريخ النشر 2018
  مجال البحث الاحصاء الرياضي
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Time-varying networks are fast emerging in a wide range of scientific and business disciplines. Most existing dynamic network models are limited to a single-subject and discrete-time setting. In this article, we propose a mixed-effect multi-subject continuous-time stochastic blockmodel that characterizes the time-varying behavior of the network at the population level, meanwhile taking into account individual subject variability. We develop a multi-step optimization procedure for a constrained stochastic blockmodel estimation, and derive the asymptotic property of the estimator. We demonstrate the effectiveness of our method through both simulations and an application to a study of brain development in youth.

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