Von Neumann-Morgenstern preferences over terminal consumption can be inferred from wealth on a single sample path when markets are complete and returns follow a known law in a neoclassical investment problem in either a discrete-time i.i.d. binomial model or a continuous-time diffusion model with a Gaussian state variable. Numerical results suggest that useful information about preferences can be obtained from even a single noisy sample of monthly observations of a portfolio over 5 years.

[Portfolio turnpike theorems show that if preferences at large wealth levels are similar to power utility, then the investment strategy converges to the power utility strategy as the horizon increases. We state and prove two simple and general portfolio turnpike theorems. Unlike existing literature, our main result does not assume independence of returns and depends only on discounting of future cash flows. We also provide a critique of portfolio turnpike results, based on the observations that (1) the time required for convergence is often too large to be relevant, and (2) there is no convergence for consumption withdrawal problems.]

Von Neumann-Morgenstern preferences over terminal consumption can be inferred from wealth on a single sample path when markets are complete and returns follow a known law in a neo-classical investment problem in either a discrete-time i.i.d. binomial model or a continuous-time diffusion model with a Gaussian state variable. Numerical results suggest that useful information about preferences can be obtained from even a single noisy sample of monthly observations of a portfolio over 5 years.

Portfolio turnpike theorems show that if preferences at large wealth levels are similar to power utility, then the investment strategy converges to the power utility strategy as the horizon increases. We state and prove two simple and general portfolio turnpike theorems. Unlike existing literature, our main result does not assume independence of returns and depends only on discounting of future cash flows. We also provide a critique of portfolio turnpike results, based on the observations that (1) the time required for convergence is often too large to be relevant, and (2) there is no convergence for consumption withdrawal problems. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.