Quality of Fit and Predictive Ability of a continuous QSAR Model
According to A. Tropsha et al. (QSAR Comb. Sci. 22 (2003) 69-77 & Mol. Inf. 2010, 29, 476-488) the following statistical criteria must be satisfied by a predictive model:
1. R2 >0.6
2. Rcvext2 >0.5
3. (R2 - R02)/R2 < 0.1
4. (R2 - R'02)/R2 < 0.1
5. abs(R02 - R'02) < 0.3
6. 0.85 ≤ k ≤ 1.15
7. 0.85 ≤ k' ≤ 1.15
where:
R2: Correlation coefficient between the predicted and observed activities
Rcvext2: External cross validation
R02: Coefficient of determination: predicted versus observed activities
R'02: Coefficient of determination: observed versus predicted activities
k = slope: predicted versus observed activities regression lines through the origin
k'= slope: observed versus predicted activities regression lines through the origin
If this node is useful to you, please cite the following papers:
Melagraki*, G., Afantitis*, A. “Enalos KNIME nodes: Exploring corrosion inhibition of steel in acidic medium” (2013) Chemometrics and Intelligent Laboratory Systems, 123, pp. 9-14. (link)
Georgia Melagraki*, Antreas Afantitis*, Enalos InSilicoNano Platform: An online decision support tool for the design and virtual screening of nanoparticles RSC Advances 2014, 4, 50713-50725 2014 (link)
Melagraki Georgia*; Afantitis Antreas* A Risk Assessment Tool for the Virtual Screening of Metal Oxide Nanoparticles through Enalos InSilicoNano Platform Current Topics in Medicinal Chemistry, Volume 15, Number 18, September 2015, pp. 1827-1836(10) 2015
E. Vrontaki, G. Melagraki*, T. Mavromoustakos, A. Afantitis*. Searching for Anthranilic Αcid-Βased Thumb Pocket 2 HCV NS5B Polymerase Inhibitors through a Combination of Molecular Docking, 3D-QSAR and Virtual Screening Journal of Enzyme Inhibition and Medicinal Chemistry DOI:10.3109/14756366.2014.1003925 (link)
KNIME Node Options:
Input Ports
0 Values for the dependent variable, predicted by the model (ypred)
1 Values for the dependent variable for the test set (yexp)
2 Values for the dependent variable for the training set (ytr)
Output Ports
0 Quality of Fit and Predictive Ability Statistics of a continuous QSAR Model
Views
Enalos Model Acceptability Criteria node provides a summary View with information about the predictive ability of model.
Download: Enalos Model Acceptability Criteria Node from: KNIME Update Community Contributions Nightly
Instructions: Open Knime, Go to Help, Install New Software, From "Available Software Sites" Select Stable Community Contributions, Select Cheminformatics (see figure) and then Select Enalos Nodes for KNIME (Enalos_nodes_for_KNIME.png)