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WEAK CONVERGENCE TO DERIVATIVES OF FRACTIONAL BROWNIAN MOTION

Published online by Cambridge University Press:  05 December 2022

Søren Johansen
Affiliation:
University of Copenhagen and CREATES
Morten Ørregaard Nielsen*
Affiliation:
Aarhus University
*
Address correspondence to Morten Ørregaard Nielsen, Department of Economics and Business Economics, Aarhus University, Aarhus, Denmark; e-mail: mon@econ.au.dk.

Abstract

It is well known that, under suitable regularity conditions, the normalized fractional process with fractional parameter d converges weakly to fractional Brownian motion (fBm) for $d>\frac {1}{2}$ . We show that, for any nonnegative integer M, derivatives of order $m=0,1,\dots ,M$ of the normalized fractional process with respect to the fractional parameter d jointly converge weakly to the corresponding derivatives of fBm. As an illustration, we apply the results to the asymptotic distribution of the score vectors in the multifractional vector autoregressive model.

Type
ARTICLES
Copyright
© The Author(s), 2022. Published by Cambridge University Press.

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Footnotes

We are grateful to the Editor (Peter C.B. Phillips) and two anonymous referees for very helpful and detailed comments. We thank the Danish National Research Foundation for financial support (DNRF Chair Grant No. DNRF154).

References

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