MODELLING STOCHASTIC VOLATILITY IN ASSET RETURNS USING FRACTIONALLY INTEGRATED SEMIPARAMETRIC TECHNIQUES
In this article we estimate the order of integration of the volatility process of several exchange rates and stock returns using fractionally integrated semiparametric techniques,namely a local Whittle semiparametric estimator. The results suggest that all series can be well described in terms of I(d) statistical models, with values of d higher than 0, indicating long-memory behaviour.