Local estimation of the Hurst index of multifractional Brownian motion by Increment Ratio Statistic method
نویسندگان
چکیده
We investigate here the Central Limit Theorem of the Increment Ratio Statistic of a multifractional Brownian motion, leading to a CLT for the time varying Hurst index. The proofs are quite simple relying on Breuer-Major theorems and an original freezing of time strategy. A simulation study shows the goodness of fit of this estimator.
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