Actors often match with associates on a small set of dimensions that matter most for the particular relationship at hand. In so doing, they are exposed to unanticipated social influences because counterparts have more interests, attitudes, and preferences than would-be associates considered when...

Social relationships channel information, influence, and access to scarce resources. As a consequence, social networks - the patterns of these relationships across the members of a community - influence who comes up with important innovations, whether and how rapidly those innovations get...