Competition in which goods or rents are allocated as a function of the various efforts expended by players in trying to win these goods or rents is a very common phenomenon. A subset of examples comes from marketing, litigation, relative reward schemes or promotion tournaments in internal labor...

Evidence from early terrorist groups reveals a structural equivalence between extortion and terrorism. This allows us to draw conclusions from the theory of extortion that can be applied to a theory of terrorism concerning the role of repeated play in the viability of extortion. It also enables...