Co-evolution models of longitudinally measured interactions

Longitudinal social networks analysis enables us to investigate interactions among group members over time. It allows to model individuals’ positions within groups and personal characteristics or attributes simultaneously and how they change over time. One of the main fundamental mechanisms of relationship formation is homophily, which means that individuals are intended to connect to someone else who is similar to them in terms of background characteristics or behavior. The question arises whether individuals select each other because they are similar or whether they do become more similar over time. Longitudinal network analysis provides the possibility to disentangle selection effects from influence effects, that is, what effects can be explained through individuals selecting specific other group members versus how individuals’ behaviors or characteristics are influenced by the interaction with others within a certain context and at a certain moment. This chapter provides a guideline how to conduct longitudinal social network analysis to analyze group interactions, including the basics of stochastic actor-based modeling.