Second Layer Map
The second Kohonen map has a smaller number of nodes - a lot of
experimentation was undertaken to find an appropriate number of
nodes. The input consists of the activation maps from the first layer
net for each of the units. The output is a series of values
representing the similarity between a unit and each of the nodes;
represented here as a bar chart. Each node of the map is isolated, so
there is no sense of topography.