Most work on social interactions studies a single, composite effect of interactions within a group. Yet in the case of sexual initiation, there are two distinct social mechanisms-peer-group norms and partner availability-with separate effects and different potential interventions. Here I develop...

In this paper, we investigate the impact of peers on own outcomes where all agents embedded in a network choose more than one activity. We develop a simple network model that illustrates these issues. We differentiate between the ‘seemingly unrelated’ simultaneous equations model where...