We investigate adaptive or evolutionary learning in a repeated version of the Grossman and Stiglit (1980) model. We demonstrate that any process that is a monotonic selection dynamic will converge to the rational expectations asset demands if the proportion of informed traders is fixed. We also show that these learning processes have a unique asymptotically stable fixed point at the Grossman–Stiglitz (GS) equilibrium. The robustness of learning to noisy experimentation is studied using Binmore and Samuelson's (1999) deterministic drift approximation. Conditions on economic and learning process parameters for adaptive learning to lead to the GS rational expectations equilibrium are presented.

ABSTRACT We characterize generalized disappointment aversion (GDA) risk preferences that can overweight lower‐tail outcomes relative to expected utility. We show in an endowment economy that recursive utility with GDA risk preferences generates effective risk aversion that is countercyclical. This feature comes from endogenous variation in the probability of disappointment in the representative agent's intertemporal consumption‐saving problem that underlies the asset pricing model. The variation in effective risk aversion produces a large equity premium and a risk‐free rate that is procyclical and has low volatility in an economy with a simple autoregressive endowment‐growth process.