wolffd@0: This directory implements Cluster Weighted Regression, as described in
wolffd@0: Neil Gershenfeld, "The nature of mathematical modelling", p182.
wolffd@0: (See also http://www.media.mit.edu/physics/publications/books/nmm/files/index.html)
wolffd@0: 
wolffd@0: Written by K. Murphy, 2 May 2003
wolffd@0: 
wolffd@0: The model is as follows:
wolffd@0: 
wolffd@0: X<--|
wolffd@0: |   Q
wolffd@0: v   |
wolffd@0: Y<--
wolffd@0: 
wolffd@0: where Q is a discrete latent mixture variable.
wolffd@0: 
wolffd@0: A mixture of experts has an X->Q arc instead of a Q->X arc;
wolffd@0: the X->Q arc is modelled by a softmax, which is slightly harder to fit than a
wolffd@0: mixture of Gaussians.
wolffd@0: 
wolffd@0: