Instituto de Economía

Abstract: “We propose a dynamic extension of max-min preferences that allows a decision maker to consider both a parametric family of what we call structured models and unstructured alternatives that are statistically close to them. The decision maker suspects that parameter values vary over time in unknown ways that he cannot describe probabilistically. He expresses suspicion that all of these parametric models are misspecified by also assessing decisions under unstructured probability distributions. We characterize equilibrium uncertainty prices by confronting a representative investor with a portfolio choice problem. We offer a quantitative illustration that focuses on the investor’s uncertainty about the size and persistence of macroeconomic growth. Nonlinearities in marginal valuations induce time variation in market prices of uncertainty. Prices of uncertainty fluctuate because a representative investor especially fears high persistence in bad states and low persistence in good ones”.