In a high-crime environment with many high-income citizens, private security companies which offer protection against crime can flourish. In this article crime is modelled as a game where richer victims yield a higher return on crime, but with decreasing returns to crime as more criminals choose...

Consider a society with a finite number of individuals. A coalition structure is a partition of the set of individuals. Each individual has personal preferences over the set of all coalition structures. We study the strategy proof core and von Neumann and Morgenstern (vN&M) solutions. A roommate...