A Wealth-Dependent Investment Opportunity Set: Its Effect on Optimal Consumption and Portfolio Decisions

Sungsub Choi
Hyeng Keun Koo
Gyoocheol Shim

and

Thaleia Zariphopoulou

We consider a consumption and investment problem where an investor’s investment opportunity gets enlarged when she becomes rich enough, i.e., when her wealth touches a critical level. We derive optimal consumption and investment rules assuming that the investor has a time-separable von Neumann-Morgenstern utility function. An interesting feature of optimal rules is that the investor consumes less and takes more risk in risky assets if the investor expects that she will have a better investment opportunity when her wealth reaches a critical level. 

Key Words: Consumption; Investment; Utility function; Brownian motion; Optimal strategy; Investment opportunity; Critical wealth level.
JEL Classification Numbers: E210, G110.