Distributionally robust shortfall risk portfolio model with moment ambiguity sets

This paper employs shortfall risk to measure portfolio risk. Assume stock returns follow polynomial relations with their influence factors. We propose a moment-based distributionally robust optimization (DRO) shortfall risk portfolio model. For piecewise linear loss functions, we show that this DRO model can be transformed into a tractable linear conic optimization problem with nonnegative polynomial cones. A Moment-SOS relaxation algorithm is proposed to solve the transformed problem. Its finite and asymptotic convergence properties are studied. For optimizers computed from our algorithm, we give convenient conditions verify their global optimality for the original DRO problem. Numerical experiments involving real stock market data are given to show the efficiency of our approach.