In Condorcet's model of information aggregation, a group of people decides among two alternatives <italic>a</italic> and <italic>b</italic>, with each person getting an independent bit of evidence about which alternative is objectively superior. I consider anonymous procedures, in which the group's decision depends only on the...

I model people in a coordination game who use a communication network to tell each other their willingness to participate. The minimal sufficient networks for coordination can be interpreted as placing people into a hierarchy of social roles or "stages": "initial adopters", then "followers", and...