To detect a likely heteroscedasticity of the error terms, the White heteroscedasticity
test is performed. The associated p-values of the F-Statistics give evidence about the existence
of heteroscedasticity in the OLS estimations. Whereas, the White test results indicate that the
null hypothesis of homoscedasticity of residuals can not be rejected at the 5 percent level in
the ARMA (1,1) estimations.