Mathematics – Statistics Theory
Scientific paper
2005-08-16
Annals of Statistics 2005, Vol. 33, No. 4, 1700-1752
Mathematics
Statistics Theory
Published at http://dx.doi.org/10.1214/009053605000000345 in the Annals of Statistics (http://www.imstat.org/aos/) by the Inst
Scientific paper
10.1214/009053605000000345
This paper explores a class of empirical Bayes methods for level-dependent threshold selection in wavelet shrinkage. The prior considered for each wavelet coefficient is a mixture of an atom of probability at zero and a heavy-tailed density. The mixing weight, or sparsity parameter, for each level of the transform is chosen by marginal maximum likelihood. If estimation is carried out using the posterior median, this is a random thresholding procedure; the estimation can also be carried out using other thresholding rules with the same threshold. Details of the calculations needed for implementing the procedure are included. In practice, the estimates are quick to compute and there is software available. Simulations on the standard model functions show excellent performance, and applications to data drawn from various fields of application are used to explore the practical performance of the approach. By using a general result on the risk of the corresponding marginal maximum likelihood approach for a single sequence, overall bounds on the risk of the method are found subject to membership of the unknown function in one of a wide range of Besov classes, covering also the case of f of bounded variation. The rates obtained are optimal for any value of the parameter p in (0,\infty], simultaneously for a wide range of loss functions, each dominating the L_q norm of the \sigmath derivative, with \sigma\ge0 and 0
Johnstone Iain M.
Silverman Bernard W.
No associations
LandOfFree
Empirical Bayes selection of wavelet thresholds does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Empirical Bayes selection of wavelet thresholds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Empirical Bayes selection of wavelet thresholds will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-131498