Un désir d'épargne... inassouvi. Essai sur les conséquences de l'escompte quasi-hyperbolique

This survey investigates the conséquences of the introduction of quasi-hyperbolic discounting (QHD) in a life-cycle model. QHD is the result of a behavioral bias (intertemporal préférences change over time) and a perception bias (the belief that the first bias is temporary). The first bias lead to suboptimal savings and excessive short-term indebtedness. The second to time inconsistency. We show how QHD can be used to explain the recent dynamics of savings and debt, which leads to a new assessment of the impact of financial deregulation. We also show how opportunistic financial agents can use the behavioral and perception biases to set up ?dutch books?. We introduce the libertarian paternalism doctrine of Thaler, Camerer and Rabin, whose aim is to reconcile two apparently irréconciliable goals : protection and freedom of choice.