16.4
Constructive Methods
Pruning methods train a larger-than-necessary network and
then remove unneeded elements. The opposite approach is to build a network
incrementally, adding elements until a suitable configuration is found. The two
approaches are complementary and often used together. Like pruning, constructive
techniques are a means of adjusting the size of a network rather than a method
for deciding what size is appropriate. Other criteria are still necessary to
decide when to stop adding elements. A number of constructive methods are
discussed in chapter 12. Cascade-correlation [120] is often cited as an
example.