This talk will be presented by Fanyuan Meng within the seminar “Analysis of complex systems” on October 8, 2021 at 3PM (CET) via Zoom.
If you would like to attend, please send an email to firstname.lastname@example.org.
Title: “A Stochastic Model of Incohesive Group Formation”
The cohesion of a social group is the group’s tendency to stick together and has important implications in the evolution of social organizations. Many empirical studies suggest that cohesion decreases with the number of group’s members. Yet, the underlying mechanism of this phenomenon is still unknown.
To investigate the relationship between group cohesion and group size, we propose a simple stochastic model of group formation where people can be of two types (fit or unfit for the group). In particular, we study the behaviour of group cohesion, defined as the fraction of members of the same type, when the group grows by recruiting new members using various admission rules.
We show that, if the admission process involves the decision (to admit or not the new candidate member) of only one member of the group, cohesion inevitably decreases with the group size. Conversely, if the admission is based on a democratic (or unanimous) decision of several group’s members, large groups can remain cohesive. Our findings help to understand the dynamics of social groups and suggest strategies to achieve high group cohesion in different contexts.
Fanyuan Meng is a Phd student in the interdisciplinary theoretical physics group led by prof Y.C. Zhang at the University of Fribourg, Switzerland. His main research interests are misinformation in social networks and signed networks.