We conducted online field experiments in large real-world social networks in order to decompose prosocial giving into three components: (1) baseline altruism toward randomly selected strangers, (2) directed altruism that favors friends over random strangers, and (3) giving motivated by the...

Advances in communication and transportation technologies have the potential to bring people closer together and create a "global village." However, they also allow heterogeneous agents to segregate along special interests, which gives rise to communities fragmented by type rather than by...

This paper builds a theory of trust based on informal contract enforcement in social networks. In our model, network connections between individuals can be used as social collateral to secure informal borrowing. We define network-based trust as the largest amount one agent can borrow from...