OPERA Model Calculation Details: Bioconcentration Factor

Structural image of 3',4-Difluoro-5'-hydroxy[1,1'-biphenyl]-2-carboxylic acid
Chemical Identifiers
Preferred name: 3',4-Difluoro-5'-hydroxy[1,1'-biphenyl]-2-carboxylic acid
DTXSID: DTXSID70689386
DTXCID: DTXCID30640135
CASRN: 1261905-38-7
Molecular weight: 250.201
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
3.24 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
0.68
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
= 0.32 ≤ 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:  3.98 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 3.55  L/kg

Structural image of 3-Hydroxy-2-naphthoic acid
3-Hydroxy-2-naphthoic acid

 Neighbor: 2
Measured:  3.02 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 6.03  L/kg

Structural image of Sodium 2-chloro-5-nitrobenzenesulphonate
Sodium 2-chloro-5-nitrobenzenesulphonate

 Neighbor: 3
Measured:  1.82 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 4.37  L/kg

Structural image of Benzilic acid
Benzilic acid

 Neighbor: 4
Measured:  3.09 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 3.24  L/kg

Structural image of 2-Carbamoyl-3,4,5,6-tetrachlorobenzoic acid
2-Carbamoyl-3,4,5,6-tetrachlorobenzoic acid

 Neighbor: 5
Measured:  5.01 L/kg
Predicted: Five fold cross validation prediction for the neighbor
 5.25  L/kg

Structural image of Sodium 3-nitrobenzenesulfonate
Sodium 3-nitrobenzenesulfonate