We study aversion to model ambiguity and misspecification in dynamic portfolio choice. Investors with relative risk aversion gamma 1 fear return persistence, while risk-tolerant investors (0 gamma 1) fear return mean reversion, to confront model misspecification concerns when facing a model...

In a market with stochastic investment opportunities, we study an optimal consumption investment problem for an agent with recursive utility of Epstein-Zin type. Focusing on the empirically relevant specification where both risk aversion and elasticity of intertemporal substitution are in excess...

When the planning horizon is long, and the safe asset grows indefinitely, iso-elastic portfolios are nearly optimal for investors who are close to iso-elastic for high wealth, and not too risk averse for low wealth. We prove this result in a general arbitrage-free, frictionless, semi-martingale...