This paper explains why people might cooperate playing an infinitely recurring prisoners' dilemma in which they change their partner in every period. After two people have played the prisoners' dilemma there is a possibility for networking. Then, two cooperators who played against each other...

This paper points out an empirical failing of real business cycle models in which unemployment is endogenized through a matching function. One can easily choose a calibration to make the cyclical fluctuation in unemployment as large in the model as it is in the data, or to make the response of...