Notes on the SWIFT method based on Shannon Wavelets for Option Pricing -- Revisited
Fabien Le Floc'h
TL;DR
This note revisits the SWIFT method, which prices European options using Shannon wavelets and a known characteristic function, with a focus on the Heston model. It analyzes quadrature choices for payoff and density, comparing Vieta-based sinc expansions to Euler–Maclaurin-corrected forms and advocating the trapezoidal rule for practical efficiency. The findings indicate that EM corrections offer limited price benefits beyond improved coefficient accuracy, while trapezoidal rules better support FFT-based implementations; nonetheless, SWIFT faces substantial computational cost in many corner cases similar to the COS method. The study provides guidance on parameter initialization and error control, highlighting that SWIFT remains robust relative to COS but requires careful handling to remain computationally viable in calibration tasks.
Abstract
This note revisits the SWIFT method based on Shannon wavelets to price European options under models with a known characteristic function in 2023. In particular, it discusses some possible improvements and exposes some concrete drawbacks of the method.
