This paper proposes a data-driven wavelet estimator for a mixture density model, in the spirit of the Goldenshluger and Lepski method. In addition, we investigate the fully adaptive estimations for multivariate density functions. First, a pointwise oracle inequality is given, which does not require any assumptions on the underlying function. Moreover, the pointwise estimation under the local Hölder condition and $ L^p $ risk ($ 1\leq p < \infty $) estimations on Besov spaces are investigated, respectively.
Citation: Kaikai Cao. Oracle inequalities and adaptive wavelet estimations for a mixture density model[J]. AIMS Mathematics, 2026, 11(9): 28628-28645. doi: 10.3934/math.20261139
This paper proposes a data-driven wavelet estimator for a mixture density model, in the spirit of the Goldenshluger and Lepski method. In addition, we investigate the fully adaptive estimations for multivariate density functions. First, a pointwise oracle inequality is given, which does not require any assumptions on the underlying function. Moreover, the pointwise estimation under the local Hölder condition and $ L^p $ risk ($ 1\leq p < \infty $) estimations on Besov spaces are investigated, respectively.
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