Table 7.

Calculation of Golbraikh and Tropsha criteria.

Parameter	Formula	Threshold	Modelscore
R ext 2	$R_{\text{ext}}^2=1-\left(\left({\displaystyle \sum {\left(Y_{\text{pred\hspace{0.17em}}\left(\text{test}\right)}-Y_{\left(\text{test}\right)}\right)}^2}\right)/\left({\displaystyle \sum {\left(Y_{\text{test}}-\overline{Y_{\text{tr}}}\right)}^2}\right)\right)$	R ext 2 > 0.6>0.6	0.75
r 2	Coefficient of determination for the plot of predicted versus observed for the test set	r 2 > 0.6	0.77
r 0 2	r 2 at zero intercept		0.71
r′02	r 2 for the plot of observed versus predicted activity for the test set at zero intercept		0.59
|r02 − r′02|		|r02 − r′02| < 0.3	0.12
k	Slope of the plot of predicted versus observed activity for the test set at zero intercept	0.85 < k < 1.15	1.07
(r2 − r02)/r2		(r2 − r02)/(r2) < 0.1	0.07
k′	Slope of the plot of observed versus predicted activity at zero intercept	0.85 < k′ < 1.15	0.92
(r2 − r′02)/r2		(r2 − r′02)/(r2) < 0.1	0.06