A neural network model of digit recognition
The top two layers form a
restricted Boltzmann machine
whose free energy landscape
models the low dimensional
manifolds of the digits.
The valleys have names:
2000 top-level units
500 units
The model learns a joint density for
labels and images. To perform
recognition we can start with a neutral
state of the label units and do one or
two iterations of the top-level RBM.
Or we can just compute the free energy
of the RBM with each of the 10 labels
500 units
28 x 28