Spatial Signal Detection Using Continuous Shrinkage Priors.
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ABSTRACT:
SUBMITTER: Jhuang AT
PROVIDER: S-EPMC6853616 | biostudies-literature | 2019
REPOSITORIES: biostudies-literature
Publications
Spatial Signal Detection Using Continuous Shrinkage Priors.
Jhuang An-Ting AT Fuentes Montserrat M Jones Jacob L JL Esteves Giovanni G Fancher Chris M CM Furman Marschall M Reich Brian J BJ
Technometrics : a journal of statistics for the physical, chemical, and engineering sciences 20190322 4
Motivated by the problem of detecting changes in two-dimensional X-ray diffraction data, we propose a Bayesian spatial model for sparse signal detection in image data. Our model places considerable mass near zero and has heavy tails to reflect the prior belief that the image signal is zero for most pixels and large for an important subset. We show that the spatial prior places mass on nearby locations simultaneously being zero, and also allows for nearby locations to simultaneously be large sign ...[more]
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