An Annotated Graph Model with Differential Degree Heterogeneity for Directed Networks

Autor: Stein, Stefan, Leng, Chenlei
Rok vydání: 2021
Předmět:
Druh dokumentu: Working Paper
Popis: Directed networks are conveniently represented as graphs in which ordered edges encode interactions between vertices. Despite their wide availability, there is a shortage of statistical models amenable for inference, specially when contextual information and degree heterogeneity are present. This paper presents an annotated graph model with parameters explicitly accounting for these features. To overcome the curse of dimensionality due to modelling degree heterogeneity, we introduce a sparsity assumption and propose a penalized likelihood approach with $\ell_1$-regularization for parameter estimation. We study the estimation and selection consistency of this approach under a sparse network assumption, and show that inference on the covariate parameter is straightforward, thus bypassing the need for the kind of debiasing commonly employed in $\ell_1$-penalized likelihood estimation. Simulation and data analysis corroborate our theoretical findings.
Comment: 69 pages, 9 figures, 4 tables. arXiv admin note: substantial text overlap with arXiv:2010.13604
Databáze: arXiv