Evolution of a large online social network

TL;DR

This paper investigates the structural evolution of a large online social network, revealing complex growth patterns, property changes, and a transition in degree correlation, providing insights into online community development.

Contribution

It offers the first detailed analysis of the evolution of a large online social network, highlighting non-trivial growth, property dynamics, and a shift in degree assortativity.

Findings

Network growth follows a non-trivial S shape.

Network properties like density and clustering show non-monotone changes.

A transition from degree assortativity to disassortativity occurs.

Abstract

Although recently there are extensive research on the collaborative networks and online communities, there is very limited knowledge about the actual evolution of the online social networks (OSN). In the Letter, we study the structural evolution of a large online virtual community. We find that the scale growth of the OSN shows non-trivial S shape which may provide a proper exemplification for Bass diffusion model. We reveal that the evolutions of many network properties, such as density, clustering, heterogeneity and modularity, show non-monotone feature, and shrink phenomenon occurs for the path length and diameter of the network. Furthermore, the OSN underwent a transition from degree assortativity characteristic of collaborative networks to degree disassortativity characteristic of many OSNs. Our study has revealed the evolutionary pattern of interpersonal interactions in a specific population and provided a valuable platform for theoretical modeling and further analysis.