We propose a new derivation of the Heath–Jarrow–Morton risk-neutral drift restriction that takes into account nonzero instantaneous correlations between factors. The result allows avoiding the orthogonalization of factors and provides an approach by which interest rate derivatives can be...

We construct multi-currency models with stochastic volatility and correlated stochastic interest rates with a full matrix of correlations. We first deal with a foreign exchange (FX) model of Heston-type, in which the domestic and foreign interest rates are generated by the short-rate process of...

The method of the Wigner-Ville function proposed by Wigner, (1932) and Ville (1947) is widely used in quantum statistical mechanics and signal processing and historically preceded the continuous-time wavelets. (Gabor, 1946) Here it is proposed for the studies of the financial time series. One of...