Efficient unbiased simulation scheme for the SABR stochastic volatility model

The stochastic Alpha Beta Rho stochastic volatility (SABR-SV) model is widely used in the financial industry for the pricing of fixed income instruments. In this paper we develop an unbiased simulation scheme for the SABR-SV model, which deals efficiently with (undesired) possible negative values, the martingale property of the discrete scheme and the discretization bias of commonly used Euler discretization schemes. The proposed algorithm is based the analytic properties of the governing distribution. Experiments with realistic model parameters show that this scheme is robust for interest rate valuation.