the pricing of European-style foreign currency options and for the volatility strike structure implicit in these contracts … is devoloped. The curvature of the volatility strike structure is explained by focusing attention on the expected … characteristic convex shape of volatility strike structures documented in the empirical literature. A volatility-based test for …

is the volatility coefficient which in turn obeys an autoregression type equation log v t = w + a S t- l + nt with an … problem of online estimation of current values of w = w(T) and a = a(T) from the observations SI , ... ,ST. We propose an … adaptive method of estimation which does not use any information about time homogeneity of the obscured process. We apply this …