Peer similarity in adolescent social networks: Types of selection and influence, and factors contributing to openness to peer influence

Peers gain heightened significance during adolescence. Youth organize themselves into peer networks that reflect clusters of social relationships, and these social networks play a prominent role in youth's risk behaviors, internalizing symptoms, and adaptive behaviors. Remarkably, youth are often quite similar to their friends, which can be because of selection and influence processes. Whereas selection refers to the process where adolescents cluster with peers based on pre-existing similarities in behaviors, attitudes, or values, influence occurs when adolescents adjust their behaviors, attitudes, or values to those of their peers. Similarity-based selection may occur through preferential attraction, default selection, and repulsion, whereas influence toward similarity may occur through mutual encouragement, imitation, peer pressure, and conformity. Most evidence has been found for selection based on preferential attraction, and influence based on imitation and norms of popular peers. Individual, dyadic, and contextual factors contributing to variations between adolescents in openness to peer influence are discussed, as well as directions for further research.