In our case, the Chi-squares (x 2) of the unconstrained model (x 2 ¼ 410.15; df ¼ 231)
was significantly lower than the Chi-squares of the constrained model (x 2 ¼ 963.85;
df ¼ 252). Given the differential of 21 degrees of freedom (Ddf ¼ 252 2 231 ¼ 21) and
a type 1 risk of 1 percent, the tabulated value of the Chi-squares is 39.932. As the
difference in Chi-squares (Dx 2 ¼ 963.85 2 410.15 ¼ 553.7) largely exceeds the
tabulated value, the discriminant validity is confirmed.