Robust consumption-investment problem under CRRA and CARA utilities with time-varying confidence sets
Zongxia Liang
Department of Mathematical Sciences, Tsinghua University, Beijing, China
Search for more papers by this authorCorresponding Author
Ming Ma
Department of Mathematical Sciences, Tsinghua University, Beijing, China
Correspondence
Ming Ma, Department of Mathematical Sciences, Tsinghua University, Beijing 100084, China.
Email: maming0292@gmail.com
Search for more papers by this authorZongxia Liang
Department of Mathematical Sciences, Tsinghua University, Beijing, China
Search for more papers by this authorCorresponding Author
Ming Ma
Department of Mathematical Sciences, Tsinghua University, Beijing, China
Correspondence
Ming Ma, Department of Mathematical Sciences, Tsinghua University, Beijing 100084, China.
Email: maming0292@gmail.com
Search for more papers by this authorAbstract
We consider a robust consumption-investment problem under constant relative risk aversion and constant absolute risk aversion utilities. The time-varying confidence sets are specified by Θ, a correspondence from [0, T] to the space of the Lévy triplets, and describe a priori drift, volatility, and jump information. For each possible measure, the log-price processes of stocks are semimartingales, and the triplet of their differential characteristics is almost surely a measurable selector from the correspondence Θ. By proposing and investigating the global kernel, an optimal policy and a worst-case measure are generated from a saddle point of the global kernel, and they constitute a saddle point of the objective function.
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