OPERA Model Calculation Details: Biodeg. Half-Life

Structural image of 1-Methyl-4-pentyl-1,2,3,4-tetrahydronaphthalene
Chemical Identifiers
Preferred name: 1-Methyl-4-pentyl-1,2,3,4-tetrahydronaphthalene
DTXSID: DTXSID80977342
DTXCID: DTXCID101404696
CASRN: 61761-57-7
Molecular weight: 216.368
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
8.71 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
0.545
Combined applicability domain:  Combined applicability domain from multiple AD measures
Outside training set (
Global AD  Global applicability domain via the leverage approach
= 0) but fair local representation (0.4 ≤
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
= 0.401 ≤ 0.6)
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:  28.8 days
Predicted: Five fold cross validation prediction for the neighbor
 15.5  days

Structural image of 9-Ethyl-9H-fluorene
9-Ethyl-9H-fluorene

 Neighbor: 2
Measured:  2.00 days
Predicted: Five fold cross validation prediction for the neighbor
 2.75  days

Structural image of 5-Methylindan
5-Methylindan

 Neighbor: 3
Measured:  22.9 days
Predicted: Five fold cross validation prediction for the neighbor
 24.5  days

Structural image of 2-Methylphenanthrene
2-Methylphenanthrene

 Neighbor: 4
Measured:  3.98 days
Predicted: Five fold cross validation prediction for the neighbor
 3.47  days

Structural image of 1,3-Dimethyl-4-ethylbenzene
1,3-Dimethyl-4-ethylbenzene

 Neighbor: 5
Measured:  5.01 days
Predicted: Five fold cross validation prediction for the neighbor
 3.55  days

Structural image of 1,2-Dimethyl-4-ethylbenzene
1,2-Dimethyl-4-ethylbenzene