“…Long-memory phenomena have been observed in numerous scientific fields such as hydrology, geophysics, economics, finance, climatology, physics, biology, medicine, music, and telecommunications engineering among others (see Hurst [23], Hosking [20], Lo [28], Willinger et al [40], Baillie [1], Lai et al [26], Hu and Øksendal [22], Granger and Hyung [19], Fleming and Kirby [18], Chronopoulou and Viens [11], Rossi and Fantazzini [35], Nguyen et al [32] and the references therein). A time series with a long-memory behavior has a slow and hyperbolically declining autocorrelation function or, equivalently, an infinite spectrum at zero frequency.…”