3.1 External
validation
External validation could well reflect the predictive performance of
ACGC model. Figure 3 expressed the scatter diagram of experimental and
calculated values for the training set and the testing set.
As was shown in Figure 3, most data
points are closely distributed along the diagonal. The data points were
well fitted both for the training set and the testing set for the
model. In addition, theR 2training and R 2test
values were 0.9891 and 0.9898 for Tc , 0.9887 and
0.9886 for Pc , 0.9983 and 0.9983 forVc , respectively. The small difference between
these two metrics clearly demonstrates the reliability of the current
model. The high correlation coefficient of the testing set demonstrated
the good prediction ability of the present models.