In this paper, we consider the Heston's volatility model (Heston in Rev. Financ. Stud. 6: 327-343, 1993]. We simulate this model using a combination of the spectral collocation method and the Laplace transforms method. To approximate the two dimensional PDE, we construct a grid which is the tensor product of the two grids, each of which is based on the Chebyshev points in the two spacial directions. The resulting semi-discrete problem is then solved by applying the Laplace transform method based on Talbot's idea of deformation of the contour integral (Talbot in IMA J. Appl. Math. 23(1): 97-120, 1979).
IntroductionThe Heston's model is one of the most popular stochastic volatility models for derivative pricing. The model leads to a more realistic option price evaluation than the celebrated Black-Scholes model and constitutes its extension to the two-dimensional form [1, 2]. In [3], Heston derived a semi-closed formula for the model; however, its implementation is not a straightforward exercise because of the oscillatory behaviour of the complex integrand which comes into play through the Fourier-type inversion formula. Therefore, we turn to numerical methods to approximate these option pricing problems.