OPERA Model Calculation Details: Bioconcentration Factor

Structural image of Brobactam
Chemical Identifiers
Preferred name: Brobactam
DTXSID: DTXSID90181175
DTXCID: DTXCID00103666
CASRN: 26631-90-3
Molecular weight: 280.14
Model Results
Model name: OPERA_BCF
Model source: OPERA2.8
Property name: Bioconcentration Factor
Property description: Bioconcentration factor: the ratio of the chemical concentration in fish as a result of absorption via the respiratory surface to that in water at steady state
Experimental value: Experimental value from OPERA2.8
 N/A
Predicted value: Predicted value from the model
3.55 L/kg
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
0.666
Combined applicability domain:  Combined applicability domain from multiple AD measures
Inside training set (
Global AD  Global applicability domain via the leverage approach
= 1) but 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
= 0.369 ≤ 0.4)
Model Performance
Bioconcentration Factor Model Results Histogram of Bioconcentration Factor Data
Weighted kNN model statistics
Training (75%) 5-fold CV (75%) Test (25%)
R2 RMSE Q2 RMSE R2 RMSE
0.85 0.53 0.84 0.55 0.83 0.64

Model summary in QSAR Model Reporting Format (QMRF)
Nearest Neighbors from Model Knowledge Base
Neighbor: 1
Measured:  2.95 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 3.63  L/kg

Structural image of 1-Naphthaleneacetic acid
1-Naphthaleneacetic acid

 Neighbor: 2
Measured:  2.29 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 4.68  L/kg

Structural image of 2,2-Dimethylpropanoic acid
2,2-Dimethylpropanoic acid

 Neighbor: 3
Measured:  2.40 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 4.37  L/kg

Structural image of Benzoic acid, 4-(methylamino)-
Benzoic acid, 4-(methylamino)-

 Neighbor: 4
Measured:  7.08 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 3.98  L/kg

Structural image of 3-Nitrobenzoic acid
3-Nitrobenzoic acid

 Neighbor: 5
Measured:  7.24 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 2.63  L/kg

Structural image of Dalapon-sodium
Dalapon-sodium