Two-step social learning strategy: from social ties to information use
Network formation and social learning on a given network both drive information transmission, yet little is known about how they interact. We use a laboratory experiment to investigate how individuals choose ties to form networks, and how the resulting social ties and networks shape information use. To do so, we introduce new methods in which social learning happens in two steps. First, social learners choose ties, and social networks result. Second, social learners make choices based on the information distributed on these networks. Participants were separated into two types to complete a learning task. Demonstrators were in self-contained networks and learned both individually and socially. Social learners first observed demonstrator networks and purchased ties to specific demonstrators. We then used the strategy method to elicit each social learner's complete strategy given her ties. Social learners prefer well-connected demonstrators, and they vary the number of ties they purchase depending on demonstrator network structure. Social learners use both success and frequency information from demonstrators, but how they do so depends on the network structure and the ties purchased. We discover that people use multiple, interacting forms of social information. Finally, comparing empirical data to optimal social learning strategies simulated using Monte Carlo simulations suggests cues about frequencies and network connections can result in sub-optimal use of social information. Our results show that people form social ties strategically, which in turn shapes social networks and how people use social information about choice frequencies and success on a network. These kinds of interactions should be critical to social transmission and cultural evolution.