Switching costs and network effects bind customers to vendors if products are incompatible, locking customers or even markets in to early choices. Lock-in hinders customers from changing suppliers in response to (predictable or unpredictable) changes in efficiency, and gives vendors lucrative ex...

Party activists wish to (i) advocate the best policy and yet (ii) unify behind a common party line. An activist`s understanding of his environment is based on the speeches of party leaders. A leader`s influence, measured by the weight placed on her speech, increases with her judgement on policy...

We construct an equilibrium random matching model of the labour market, with endogenous market participation and a general matching technology that allows for market size effects: the job-finding rate for workers and the incentives for participation change with the level of unemployment. In...