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arXiv · 2004.03417

Nonparametric Estimation for I.I.D. Paths of Fractional SDE

Fabienne Comte·Nicolas Marie
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Abstract

This paper deals with nonparametric estimators of the drift function $b$ computed from independent continuous observations, on a compact time interval, of the solution of a stochastic differential equation driven by the fractional Brownian motion (fSDE). First, a risk bound is established on a Skorokhod's integral based least squares oracle $\widehat b$ of $b$. Thanks to the relationship between the solution of the fSDE and its derivative with respect to the initial condition, a risk bound is deduced on a calculable approximation of $\widehat b$. Another bound is directly established on an estimator of $b'$ for comparison. The consistency and rates of convergence are established for these estimators in the case of the compactly supported trigonometric basis or the $\mathbb R$-supported Hermite basis.

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BibTeXRIS

Fabienne Comte, Nicolas Marie. 2020-04-04. Nonparametric Estimation for I.I.D. Paths of Fractional SDE. https://doi.org/10.1007/s11203-021-09246-4

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