"A New Improvement Scheme for Approximation Methods of Probability Density Functions"
This paper develops a new scheme for improving an approximation method of a probability density function, which is inspired by the idea in <I>best approximation in an inner product space</I>. Moreover, we applies "Dykstra's cyclic projections algorithm" for its implementation. Numerical examples for application to an asymptotic expansion method in option pricing demonstrate the effectiveness of our scheme under Black-Scholes and SABR models.