Heterogeneity shapes groups growth in social online communities

TL;DR

This paper investigates how intrinsic heterogeneity influences the growth of groups in online communities, demonstrating that it, combined with simple growth dynamics, explains the broad distribution of group sizes.

Contribution

It provides empirical evidence on group heterogeneity and introduces a model combining heterogeneity, linear growth, and inhomogeneous birth rates to explain group size distributions.

Findings

Heterogeneity significantly impacts group growth patterns.

A simple model with heterogeneity and inhomogeneous birth rates reproduces observed distributions.

Empirical data supports the role of heterogeneity in social online communities.

Abstract

Many complex systems are characterized by broad distributions capturing, for example, the size of firms, the population of cities or the degree distribution of complex networks. Typically this feature is explained by means of a preferential growth mechanism. Although heterogeneity is expected to play a role in the evolution it is usually not considered in the modeling probably due to a lack of empirical evidence on how it is distributed. We characterize the intrinsic heterogeneity of groups in an online community and then show that together with a simple linear growth and an inhomogeneous birth rate it explains the broad distribution of group members.