A closed-form pricing formula for variance swaps under MRG–Vasicek model

In this paper, the pricing problems of variance swaps with discrete sampling times are studied, where the volatility of underlying assets follows a mean-reverting Gaussian (MRG in short) process, and the instantaneous interest rate is described by classical Vasicek model. By using measure transformation, Feynman–Kac formula and Fourier transform algorithm, a closed-form analytic pricing formula for variance swaps with the actual-return realized variance is presented.