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Perfect simulation for Bayesian wavelet thresholding with correlated coefficients

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 نشر من قبل Bernard Silverman
 تاريخ النشر 2009
  مجال البحث الاحصاء الرياضي
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We introduce a new method of Bayesian wavelet shrinkage for reconstructing a signal when we observe a noisy version. Rather than making the common assumption that the wavelet coefficients of the signal are independent, we allow for the possibility that they are locally correlated in both location (time) and scale (frequency). This leads us to a prior structure which is analytically intractable, but it is possible to draw independent samples from a close approximation to the posterior distribution by an approach based on Coupling From The Past.



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