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CT-AI · Question #14

Upon testing a model used to detect rotten tomatoes, the following data was observed by the test engineer, based on certain number of tomato images. For this confusion matrix which combinations of…

The correct answer is A. 0.87.0.9. 0.84. To calculate the accuracy, recall, and specificity from the confusion matrix provided, we use the following formulas: Confusion Matrix: Actually Rotten: 45 (True Positive), 8 (False Positive) Actually Fresh: 5 (False Negative), 42 (True Negative) Accuracy is the proportion of…

Testing, Debugging, and Deployment

Question

Upon testing a model used to detect rotten tomatoes, the following data was observed by the test engineer, based on certain number of tomato images. For this confusion matrix which combinations of values of accuracy, recall, and specificity respectively is CORRECT?

Exhibit

CT-AI question #14 exhibit

Options

  • A0.87.0.9. 0.84
  • B1,0.87,0.84
  • C1,0.9, 0.8
  • D0.84.1,0.9

How the community answered

(37 responses)
  • A
    70% (26)
  • B
    5% (2)
  • C
    16% (6)
  • D
    8% (3)

Explanation

To calculate the accuracy, recall, and specificity from the confusion matrix provided, we use the following formulas: Confusion Matrix: Actually Rotten: 45 (True Positive), 8 (False Positive) Actually Fresh: 5 (False Negative), 42 (True Negative) Accuracy is the proportion of true results (both true positives and true negatives) in the total Formula: Accuracy=TP+TNTP+TN+FP+FN\text{Accuracy} = \frac{TP + TN}{TP + TN + FP + FN}Accuracy=TP+TN+FP+FNTP+TN Calculation: Accuracy=45+4245+42+8+5=87100=0.87\text{Accuracy} = \frac{45 + 42}{45 + 42 + 8 + 5} = \frac{87}{100} = 0.87Accuracy=45+42+8+545+42=10087=0.87 Recall (Sensitivity): Recall is the proportion of true positive results in the total actual positives. Formula: Recall=TPTP+FN\text{Recall} = \frac{TP}{TP + FN}Recall=TP+FNTP Calculation: Recall=4545+5=4550=0.9\text{Recall} = \frac{45}{45 + 5} = \frac{45}{50} = 0.9Recall=45+545=5045=0.9 Specificity is the proportion of true negative results in the total actual negatives. Formula: Specificity=TNTN+FP\text{Specificity} = \frac{TN}{TN + FP}Specificity=TN+FPTN Calculation: Specificity=4242+8=4250=0.84\text{Specificity} = \frac{42}{42 + 8} = \frac{42}{50} = 0.84Specificity=42+842=5042=0.84 Therefore, the correct combinations of accuracy, recall, and specificity are 0.87, 0.9, and 0.84

Topics

#confusion matrix#accuracy#recall#specificity

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