Saved in:
Bibliographic Details
Main Authors: Jiang, Stephen, Fan, Jianqing
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2410.07621
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917839904964608
author Jiang, Stephen
Fan, Jianqing
author_facet Jiang, Stephen
Fan, Jianqing
contents With the rise of big data, networks have pervaded many aspects of our daily lives, with applications ranging from the social to natural sciences. Understanding the latent structure of the network is thus an important question. In this paper, we model the network using a Degree-Corrected Mixed Membership (DCMM) model, in which every node $i$ has an affinity parameter $θ_i$, measuring the degree of connectivity, and an intrinsic membership probability vector $π_i = (π_1, \cdots π_K)$, measuring its belonging to one of $K$ communities, and a probability matrix $P$ that describes the average connectivity between two communities. Our central question is to determine the optimal estimation rates for the probability matrix and degree parameters $P$ and $Θ$ of the DCMM, an often overlooked question in the literature. By providing new lower bounds, we show that simple extensions of existing estimators in the literature indeed achieve the optimal rate. Simulations lend further support to our theoretical results.
format Preprint
id arxiv_https___arxiv_org_abs_2410_07621
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Optimal Estimation of Parameters in Degree Corrected Mixed Membership Models
Jiang, Stephen
Fan, Jianqing
Statistics Theory
With the rise of big data, networks have pervaded many aspects of our daily lives, with applications ranging from the social to natural sciences. Understanding the latent structure of the network is thus an important question. In this paper, we model the network using a Degree-Corrected Mixed Membership (DCMM) model, in which every node $i$ has an affinity parameter $θ_i$, measuring the degree of connectivity, and an intrinsic membership probability vector $π_i = (π_1, \cdots π_K)$, measuring its belonging to one of $K$ communities, and a probability matrix $P$ that describes the average connectivity between two communities. Our central question is to determine the optimal estimation rates for the probability matrix and degree parameters $P$ and $Θ$ of the DCMM, an often overlooked question in the literature. By providing new lower bounds, we show that simple extensions of existing estimators in the literature indeed achieve the optimal rate. Simulations lend further support to our theoretical results.
title Optimal Estimation of Parameters in Degree Corrected Mixed Membership Models
topic Statistics Theory
url https://arxiv.org/abs/2410.07621