The sigmoid is the poserior distribution from Gaussian likelihoods

[B344DSL@UTARLG.UTA.EDU]

I think there was some remark about the sigmoid as the distribution function
arising from a Gaussian density in Grossberg's paper in Studies in Applied Math,1973, and/or in one of those paper's two direct sequels: by Ellias and Gross-
berg in Biological Cybernetics 1975, and Grossberg and Levine in Journal of
Theoretical Biology 1975.

Dan Levine