Table 2 Internal validation of the five (5) QSAR models
Parameters | Model 1 | Model 2 | Model 3 | Model 4 | Model 5 | Threshold |
|---|---|---|---|---|---|---|
Friedman (LOF) | 0.8669 | 0.9431 | 0.9408 | 0.9376 | 1.4731 | – |
R-squared (training set) | 0.8563 | 0.8436 | 0.8440 | 0.8446 | 0.7234 | > 0.6 |
Adjusted R-squared | 0.8185 | 0.8025 | 0.8030 | 0.8037 | 0.6542 | > 0.6 |
Cross validated (Q2cv) | 0.7543 | 0.7315 | 0.7423 | 0.6620 | 0.5781 | > 0.5 |
Standard error of estimation (SEE) | 0.4336 | 0.4522 | 0.4517 | 0.4509 | 0.5671 | – |
Variance ratio (F value) | 22.648 | 20.5100 | 20.5700 | 20.6538 | 10.4625 | – |
PRESS | 3.5724 | 3.8866 | 3.8775 | 3.8638 | 6.4323 | > 0.5 |
Average \( {\overline{R}}_m^2 \) (LOO-train) | 0.6751 | 0.6501 | 0.6564 | 0.5721 | 0.4771 | > 0.5 |
Delta \( {\overline{R}}_m^2 \) (LOO-train) | 0.0898 | 0.0680 | 0.1184 | 0.0971 | 0.0755 | – |
Computed experimental error | 0.1044 | 0.1044 | 0.1044 | 0.1044 | 0.1 | – |
RMSEP | 1.0657 | 1.1101 | 1.1320 | 0.9995 | 0.3388 | – |
Y randomization (C\( {R}_{\mathrm{p}}^2\Big) \) | 0.7609 | 0.7392 | 0.7468 | 0.7516 | 0.6296 | > 0.5 |