Waves of Optimism and Pessimism

Abstract

We consider a simple consumption-based asset pricing model with two types of investors who have access to the same observations but who use different updating rules to infer information about the growth state of the economy. In particular, we consider an optimistic and pessimistic group of agents who use distorted Bayesian updating rules. The aim of the work is to understand to what extent the interaction of such distorted Bayesian rules can explain low and medium frequency characterization of dynamics movements observed in the price dividend ratios and can give rise endogenously to waves of pessimism and optimism which are associated with sustained asset price booms and busts. The analysis shows that heterogeneity in ambiguity loving/aversion preferences appears to be an important factor to capture medium-frequency waves observed on asset prices.