Higher-Order Interactions in Social Systems

The de facto representation of a social network is a graph— individuals are represented as nodes, and relationships between pairs of individuals are represented as edges. This results in a powerful abstraction by which social relationships can be systematically studied to understand emergent population-scale behavior. However, many social interactions occur in groups: three individuals may co-author a paper, a team of employees may collaborate on a task, a single tweet may mention four users. Breaking such interactions into a collection of pairwise relationships can oversimplify the rich social contexts in which these individuals know one another. This thesis explores a different paradigm of social network analysis, namely, using "higher-order" network models such as hypergraphs and simplicial complexes which can explicitly encode co-present contexts between three or more individuals. The first two projects describe how higher-order interactions can differ from pairwise interactions in terms of micro-level content and macro-level structure, respectively. The latter two projects then develop an applied mathematical toolkit for the algebraic topological analysis of higher-order interactions in social networks.

Name thesis:degree_name

Doctoral

Department dc:contributor.department

Massachusetts Institute of Technology. Institute for Data, Systems, and Society

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2025

Author dc:creator

• Sarker, Arnab Kumar

Advisor dc:contributor.advisor

• Jadbabaie, Ali

Statement dc:rights

• In Copyright - Educational Use Permitted
• Copyright retained by author(s)

Licence dc:rights.uri

• https://rightsstatements.org/page/InC-EDU/1.0/

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/159095

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/159095