Consider a group of economists evaluating a long-term project by using quasi- hyperbolic rules. The parameters (discount rates and present bias) used by each economist may differ, which implies different policy recommendations. Then a policy maker has to choose a socially efficient aggregation...

This paper studies the existence of equilibrium solution concepts in a large class of economic models with discontinuous payoff functions. The issue is well understood for Nash equilibria, thanks to Reny’s better-reply security con- dition ( Reny 1999) and its recent improvements (Barelli and...