Test of constant variance of the error terms (Homoscedsticity)
Homoscedasticity means that the variance of errors is the same cross all levels the independent variable. This research is checked by visual examination of a plot of the standardized residuals by regression standardized predicted value. Preferably, residuals are randomly scattered around 0 (the horizontal line ) providing a relatively even distribution. To consider the constant variance fo error terms, plotting the residual gainst the predicted dependent values id used for verification. As a result the heteroscedasticity problems should not be concerned. This finding indicates homoscedasticity in the set of independent variable. The following shows the residual plots for linearity and constant variance of error terms testing