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 proposes a model of intertemporal preferences where the relative risk aversion depends on the time horizon of the agent. The agent is supposed to evaluate risk in the short run with a relative risk aversion coefficient which differs from its long run value. As preferences are no more...