EMPIRICAL BAYES THRESHOLDING: ADAPTING TO SPARSITY WHEN IT ADVANTAGEOUS TO DO SO

  • Silverman Bernard W. (St Peter's College, University of Oxford)
  • Published : 2007.03.31

Abstract

Suppose one is trying to estimate a high dimensional vector of parameters from a series of one observation per parameter. Often, it is possible to take advantage of sparsity in the parameters by thresholding the data in an appropriate way. A marginal maximum likelihood approach, within a suitable Bayesian structure, has excellent properties. For very sparse signals, the procedure chooses a large threshold and takes advantage of the sparsity, while for signals where there are many non-zero values, the method does not perform excessive smoothing. The scope of the method is reviewed and demonstrated, and various theoretical, practical and computational issues are discussed, in particularly exploring the wide potential and applicability of the general approach, and the way it can be used within more complex thresholding problems such as curve estimation using wavelets.

Keywords

References

  1. ANTONIADIS, A., JANSEN, M., JOHNSTONE, I. M. AND SILVERMAN, B. W. (2004). EbayesThresh: MATLAB software for Empirical Bayes thresholding, http://www-lmc.imag.fr/Imc-sms/Anestis.Antoniadis/EBayesThresh
  2. COIFMAN, R. R. AND DONOHO, D. L. (1995). Translation-invariant de-noising, (A. Antoniadis, ed), Wavelets and Statistics, Lecture Notes in Statistics, Springer
  3. DONOHO, D. L. AND JOHNSTONE, I. M. (1994a). 'Minimax risk over $l_p-balls\;for\;l_q-error$', Probability Theory and Related Fields, 99, 277-303 https://doi.org/10.1007/BF01199026
  4. DONOHO, D. L. AND JOHNSTONE, I. M: (1994b). 'Idle spatial adaptation by wavelet shrinkage', Biometrika, 81, 425-455 https://doi.org/10.1093/biomet/81.3.425
  5. JANSEN, M., NASON, G. P. AND SILVERMAN, B. W. (2004). 'Multivariate nonparametric regression using lifting', Technical Report 04:17, Department of Mathematics, University of Bristol, http://www.maths.bris.ac.uk/research/ stats/pub/ResRept/2004.html
  6. JOHNSTONE, I. M. AND SILVERMAN, B. W. (2004a). 'Needles and straw in haystacks: empirical Bayes estimates of possibly sparse sequences', The Annals of Statistics, 32, 1594-1649 https://doi.org/10.1214/009053604000000030
  7. JOHNSTONE, I. M. AND SILVERMAN, B. W. (2005a). 'EbayesThresh: R programs for empirical Bayes thresholding', Journal of Statistical Software, 12, 1-38
  8. JOHNSTONE, I. M. AND SILVERMAN, B. W. (2005b). 'Empirical Bayes selection of wavelet thresholds', Annals of Statistics, 33, 1700-1752 https://doi.org/10.1214/009053605000000345
  9. Johnstone, I. M. and Silverman, B. W. (2004b). 'Boundary coiflets for wavelet shrinkage in function estimation', Journal of Applied Probability, 41A, 81-98 https://doi.org/10.1239/jap/1082552192
  10. JOHNSTONE, I. M. AND SILVERMAN, B. W. (1997). 'Wavelet threshold estimators for data with correlated noise', Journal of the Royal Statistical Society, Ser. B, 59, 319-351 https://doi.org/10.1111/1467-9868.00071
  11. NASON, G. P. (1996). 'Wavelet shrinkage using cross-validation', Journal of the Royal Statistical Society, Ser. B, 58, 463-479
  12. NASON, G. P. (1998). WaveThresh3 Software, Department of Mathematics, University of Bristol, Bristol, U.K.
  13. SILVERMAN, B. W. (2005). EbayesThresh: Empirical Bayes thresholding and related methods, CRAN