
196
Chapter 11
input to an intermediate level, it is first clamped to one extreme, then
the other. If the output neuron corresponding to a certain class tends
to become more activated (across the training set) when the input is
clamped fully activated, then it appears that activation of that input
is a feature important to classification into that class. Due to the
unpredictable nature of interactions among inputs, this is a dangerous
technique and is easily abused.
Another version of sensitivity analysis presents a case to the
network, then observes the effect of varying individual inputs while all
others are fixed. Changing some inputs ma ...