Evolutionary strategic beliefs and financial markets

Elyès Jouini (1) , Clotilde Napp (2, 3) , Yannick Viossat (1)

1 CEREMADE - CEntre de REcherches en MAthématiques de la DEcision
2 CREST - Centre de Recherche en Économie et Statistique
3 DRM - Dauphine Recherches en Management

We provide a discipline for belief formation through a model of subjective beliefs, in which agents hold strategic beliefs. More precisely, we consider beliefs as a strategic variable that agents can choose (consciously or not) in order to maximize their utility at the equilibrium. These strategic beliefs result from an evolutionary process. We find that evolutionary strategic behavior leads to belief subjectivity and heterogeneity. Optimism (resp. overconfidence) as well as pessimism (resp. doubt) both emerge from the evolution process. Furthermore, we obtain a positive correlation between pessimism (rep. doubt) and risk-tolerance. We analyse the equilibrium characteristics. Under reasonable assumptions, the consensus belief is pessimistic and, as a consequence, the risk premium is higher than in a standard setting.

Mots clés: Beliefs formation; strategic beliefs; optimal beliefs; distorded beliefs; pessimism; risk premium

Domaines: Economies et finances

Elyès Jouini, Clotilde Napp, Yannick Viossat. Evolutionary strategic beliefs and financial markets. Review of Finance, 2012, pp.1. ⟨halshs-00556490⟩