Before revision:  We define a novel estimator of the effect which is based on a pre-estimation of the Fourier coefficients of the return and of the volatility process as defined in Malliavin and Mancino (2002).
After revision:  A novel estimator of the effect which is based on a pre-estimation of the Fourier coefficients of the return and of the volatility process as defined in Malliavin and Mancino (2002).