Abstract
Methods of robust estimation in diffusion processes are given by means of M-estimation. It is shown that the asymptotic variance of an M-estimator is obtained by applying a certain integral operator to the influence function and integrating its square. Under the condition of boundedness of the influence function, the existence of an optimal robust M-estimator is shown and an approximately optimal practical method is given. Moreover, as another criterion of robustness we consider a norm of integral type and show that the corresponding optimal robust M-estimator is obtained by solving a boundary value problem of a second order differential equation. Finally, as an illustrative example the Ornstein-Uhlenbeck process is discussed.
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Yoshida, N. Robust M-estimators in diffusion processes. Ann Inst Stat Math 40, 799–820 (1988). https://doi.org/10.1007/BF00049433
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DOI: https://doi.org/10.1007/BF00049433