OPERA Model Calculation Details: Biodeg. Half-Life

Structural image of Disodium carbonate heptahydrate
Chemical Identifiers
Preferred name: Disodium carbonate heptahydrate
DTXSID: DTXSID3051385
DTXCID: DTXCID4029987
CASRN: 56399-31-6
Molecular weight: 232.093
Model Results
Model name: OPERA_BioDeg
Model source: OPERA2.8
Property name: Biodeg. Half-Life
Property description: Biodegradation half-life for compounds containing only carbon and hydrogen
Experimental value: Experimental value from OPERA2.8
 N/A
Predicted value: Predicted value from the model
7.59 days
Confidence level:  Confidence level is calculated from the accuracy of the predictions of the five nearest neighbors weighted by their distance to the query chemical
0.672
Combined applicability domain:  Combined applicability domain from multiple AD measures
Outside training set (
Global AD  Global applicability domain via the leverage approach
= 0) and poor local representation (
Local AD index Local applicability domain index is relative to the similarity of the query chemical to its five nearest neighbors from the training set
= 0.264 < 0.4)
Model Performance
Biodeg. Half-Life Model Results Histogram of Biodeg. Half-Life Data
Weighted kNN model statistics
Training (75%) 5-fold CV (75%) Test (25%)
R2 RMSE Q2 RMSE R2 RMSE
0.88 0.26 0.89 0.25 0.75 0.38

Model summary in QSAR Model Reporting Format (QMRF)
Nearest Neighbors from Model Knowledge Base
Neighbor: 1
Measured:  5.01 days
Predicted: Five fold cross validation prediction for the neighbor
 8.32  days

Structural image of Pentane
Pentane

 Neighbor: 2
Measured:  8.91 days
Predicted: Five fold cross validation prediction for the neighbor
 6.03  days

Structural image of n-Hexane
n-Hexane

 Neighbor: 3
Measured:  7.08 days
Predicted: Five fold cross validation prediction for the neighbor
 7.94  days

Structural image of Heptane
Heptane

 Neighbor: 4
Measured:  8.91 days
Predicted: Five fold cross validation prediction for the neighbor
 7.76  days

Structural image of Octane
Octane

 Neighbor: 5
Measured:  8.91 days
Predicted: Five fold cross validation prediction for the neighbor
 8.32  days

Structural image of Nonane
Nonane