Abstract
In this note, we consider the problem of aggregation of estimators in order to denoise a signal. The main contribution is a short proof of the fact that the exponentially weighted aggregate satisfies a sharp oracle inequality. While this result was already known for a wide class of symmetric noise distributions, the extension to asymmetric distributions presented in this note is new.
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Notes
This means that the density of \(\xi_{i}\) is equal to \((2\mu_{i})^{-1}\exp(-|x|/\mu_{i})\).
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The work of the author was supported by the grant Investissements d’Avenir (ANR-11-IDEX-0003/Labex Ecodec/ANR-11-LABX-0047), the FAST Advance grant and the center Hi! PARIS.
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Dalalyan, A.S. Simple Proof of the Risk Bound for Denoising by Exponential Weights for Asymmetric Noise Distributions. J. Contemp. Mathemat. Anal. 58, 391–399 (2023). https://doi.org/10.3103/S106836232306002X
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DOI: https://doi.org/10.3103/S106836232306002X