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Optimal change-point estimation from indirect observations

A. Goldenshluger·A. Tsybakov·A. Zeevi
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Abstract

We study nonparametric change-point estimation from indirect noisy observations. Focusing on the white noise convolution model, we consider two classes of functions that are smooth apart from the change-point. We establish lower bounds on the minimax risk in estimating the change-point and develop rate optimal estimation procedures. The results demonstrate that the best achievable rates of convergence are determined both by smoothness of the function away from the change-point and by the degree of ill-posedness of the convolution operator. Optimality is obtained by introducing a new technique that involves, as a key element, detection of zero crossings of an estimate of the properly smoothed second derivative of the underlying function.

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A. Goldenshluger, A. Tsybakov, A. Zeevi. 2006-05-18. Optimal change-point estimation from indirect observations. https://doi.org/10.1214/009053605000000750

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