Pointwise optimality of Bayesian wavelet estimators

نویسندگان

  • Felix Abramovich
  • Claudia Angelini
  • Daniela De Canditiis
چکیده

We consider pointwise mean squared errors of several known Bayesian wavelet estimators, namely, posterior mean, posterior median and Bayes Factor, where the prior imposed on wavelet coefficients is a mixture of an atom of probability zero and a Gaussian density. We show that for the properly chosen hyperparameters of the prior, all the three estimators are (up to a log-factor) asymptotically minimax within any prescribed Besov ball Bp,q(M). We discuss the Bayesian paradox and compare the results for the pointwise squared risk with those for the global mean squared error.

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تاریخ انتشار 2007