Although ANN does not depend on the multivariate characteristics of the data , we also examined the data to assess whether they were homoscedastic or heteroscedastic because this allowed us to understand the nature of the data more fully . We employed two approaches for this purpose - first , by using the Glejser test for heteroscedasticity ( Glejser , 1969 ) and , second , by plotting the standardised regression residuals and the dependent variables ( Figs . 2 and 3 ) . Visual inspection confirmed the data to be homoscedastic .