The initialisation of a neural network implementation of Sammon's mapping,
either randomly or based on the principal components (PCs) of the sample co
variance matrix, is experimentally investigated. When PCs are employed, few
er experiments are needed and the network configuration can be set precisel
y without trial-and-error experimentation. Tested on five real-world databa
ses, it is shown chat very few PCs are required to achieve a shorter traini
ng period, lower mapping error and higher classification accuracy, compared
with those based on random initialisation.