Optimal Damping with Hierarchical Adaptive Quadrature for Efficient Fourier Pricing of Multi-Asset Options in Lévy Models

Efficient pricing of multi-asset options is a challenging problem in quantitative finance. When the Fourier transform of the density function is available, Fourier-based pricing methods become very competitive compared to alternative techniques because the integrand in the frequency space has often higher regularity than in the physical space. However, when designing a numerical quadrature method for most of these Fourier pricing approaches, two key aspects affecting the numerical complexity should be carefully considered: (i) the choice of the damping parameters that ensure integrability and control the regularity class of the integrand and (ii) the effective treatment of the high dimensionality of the integration problem. To address these challenges, based on the extension of the one-dimensional Fourier valuation formula to the multivariate case, we propose an efficient numerical method for pricing European multi-asset options based on two complementary ideas. First, we smooth the Fourier integrand via an optimized choice of damping parameters based on a proposed heuristic optimization rule. Second, we use the adaptive sparse grid quadrature based on sparsification and dimension-adaptivity techniques to accelerate the convergence of the numerical quadrature in high dimensions. Through an extensive numerical study on the basket and rainbow options under the multivariate geometric Brownian motion and some multivariate L\'evy models, we demonstrate the advantages of adaptivity and our damping parameter rule on the numerical complexity of the quadrature methods. Moreover, we reveal that our approach achieves substantial computational gains compared to the Monte Carlo method for different dimensions and parameter constellations.