The Use of Sieves to Stabilize Images Produced with the EM Algorithm for Emission Tomography

  title={The Use of Sieves to Stabilize Images Produced with the EM Algorithm for Emission Tomography},
  author={D. Snyder and M. Miller},
  journal={IEEE Transactions on Nuclear Science},
Images produced in emission tomography with the expectation-maximization (EM) algorithm have been observed to become more 'noisy' as the algorithm converges towards the maximum-likelihood estimate. We argue in this paper that there is an instability which is fundamental to maximum-likelihood estimation as it is usually applied and, therefore, is not a result of using the EM algorithm, which is but one numerical implementation for producing maximum-likelihood estimates. We show how Grenader's… Expand
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  • J. Ollinger
  • Physics, Computer Science
  • IEEE Trans. Medical Imaging
  • 1994
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