S/NO | Validation parameters | Formula | Threshold | Model 1 | Model 2 |
---|---|---|---|---|---|
Internal validation | |||||
1 | Friedman’s lack of fit (LOF) | \( \frac{SEE}{{\left(1-\frac{w+q\times j}{N}\right)}^2} \) |  | 0.0274 | 0.0301 |
2 | R-squared | \( 1-\left[\frac{\sum {\left({Y}_{obs\kern0.5em -{Y}_{pred}}\right)}^2}{\sum {\left({Y}_{obs\kern0.5em -{\overline{Y}}_{training}}\right)}^2}\right] \) | R2 > 0.6 | 0.9183 | 0.8429 |
3 | Adjusted R-squared | \( \frac{R^2-P\ \left(N-1\right)}{N-p+1} \) | \( {R}_{\mathrm{adj}}^2>0.6 \) | 0.8854 | 0.8189 |
4 | Cross validated R-squared (\( {Q}_{cv}^2\Big) \) | \( 1-\left[\frac{\sum {\left({Y}_{pred\kern0.5em -{Y}_{obs}}\right)}^2}{\sum {\left({Y}_{obs\kern0.5em -{\overline{Y}}_{training}}\right)}^2}\right] \) | Q2 > 0.6 | 0.8202 | 0.7400 |
5 | Significant regression | Â | Â | Yes | Yes |
6 | Critical SOR F value (95%) | \( \frac{\sum {\left({Y}_{pred\kern0.5em -{Y}_{obs}}\right)}^2}{p}/\frac{\sum {\left({Y}_{pred\kern0.5em -{Y}_{obs}}\right)}^2}{N-p-1} \) | F(test) > 2.09 | 4.3892 | 4.3892 |
7 | Replicate points | Â | Â | 0 | 0 |
8 | Computed observed error | Â | Â | 0 | 0 |
9 | Min expt. error for non-significant LOF (95%) | Â | Â | 0.0278 | 0.0278 |
Model randomization | |||||
10 | Average of the correlation coefficient for randomized data (\( {\overline{R}}_r \)) | Â | \( \overline{R}<0.5 \) | 0.3371 | 0.3983 |
11 | Average of determination coefficient for randomized data (\( {\overline{R}}_r^2\Big) \) | Â | \( {\overline{\mathrm{R}}}_r^2<0.5 \) | 0.1521 | 0.1763 |
12 | Average of leave-one-out cross-validated determination coefficient for randomized data (\( {\overline{Q}}_r^2 \)) |  | \( {\overline{Q}}_r^2<0.5 \) | − 1.3198 | − 1.3719 |
13 | Y-randomization coefficient (c\( {R}_p^2\Big) \) | \( {R}^2\times \left(1-\sqrt{\left|{R}^2-{\overline{R}}_{\mathrm{r}}^2\right|}\ \right) \) | c\( {R}_{\mathrm{p}}^2>0.6 \) | 0.7362 | 0.7058 |
External validation | |||||
14 | Slope of the plot of observed activity against predicted activity values at zero intercept (K) | \( \frac{\boldsymbol{\Delta }{\boldsymbol{Y}}_{\boldsymbol{Obs}}}{{\boldsymbol{\Delta Y}}_{\boldsymbol{pred}}} \) | 0.85 < k < 1.15 | 1.0013 | 1.0582 |
15 | Slope of the plot of predicted against observed activity at zero intercept (k′) | \( \frac{\boldsymbol{\Delta }{\boldsymbol{Y}}_{\boldsymbol{pred}}}{\boldsymbol{\Delta }{\boldsymbol{Y}}_{\boldsymbol{Obs}}} \) | 0.85 < k < 1.15 | 0.9290 | 0.9016 |
16 | \( /{\boldsymbol{r}}_{\mathbf{0}}^{\mathbf{2}}-{{\boldsymbol{r}}^{\prime}}_{\mathbf{0}}^{\mathbf{2}}/ \) | Â | < 0.3 | 0.0834 | 0.0610 |
17 | \( \frac{{\boldsymbol{r}}^{\mathbf{2}}-{\boldsymbol{r}}_{\mathbf{0}}^{\mathbf{2}}}{{\boldsymbol{r}}^{\mathbf{2}}} \) | Â | < 0.1 | 0.0028 | 0.0042 |
18 | \( \frac{{\boldsymbol{r}}^{\mathbf{2}}-{{\boldsymbol{r}}^{\prime}}_{\mathbf{0}}^{\mathbf{2}}}{{\boldsymbol{r}}^{\mathbf{2}}} \) | Â | < 0.1 | 0.0610 | 0.0582 |
19 | \( {\boldsymbol{R}}_{\mathbf{test}}^{\mathbf{2}} \) | \( {R}_{test}^2=1-\frac{\sum {\left(Y{pred}_{test}-{Y}_{obs_{test}}\right)}^2}{\sum {\left(Y{pred}_{test}-{\overline{Y}}_{training}\ \right)}^2} \) | >0.6 | 0.8052 | 0.7281 |