The :param:`SPREAD_MODEL` estimator has been developed as a star/galaxy classifier for the DESDM pipeline :cite:`2012SPIE_8451E_0DM`, and has also been used in other surveys :cite:`2012ApJ_757_83D,2013AA_554A_101B`.
:param:`SPREAD_MODEL` indicates which of the best fitting local PSF model resampled at the current position :math:`\tilde{\boldsymbol{\phi}}` (representing a point source) or a slightly ``fuzzier'' resampled model :math:`\tilde{\boldsymbol{G}}` (representing a galaxy) matches best the image data.
:param:`SPREAD_MODEL` indicates which of the best fitting local PSF model resampled at the current position :math:`\tilde{\boldsymbol{\phi}}` (representing a point source) or a slightly "fuzzier" resampled model :math:`\tilde{\boldsymbol{G}}` (representing a galaxy) matches best the image data.
:math:`\tilde{\boldsymbol{G}}` is obtained by convolving the local PSF model with a circular exponential model with scalelength = 1/16 |FWHM|, and resampling the result at the current position on the pixel grid. :param:`SPREAD_MODEL` is normalized to allow comparing sources with different PSFs throughout the field:
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@@ -306,6 +306,7 @@ In order to maintain a certain level of purity or completeness across the whole