Certified Tester AI Testing
Domain 5Objective 1
Confusion Matrix CT-AI Practice Questions (Page 1)
Part of the Domain 5: ML Functional Performance Metrics domain, which makes up ~5% of our current practice bank. ISTQB does not publish an official question count, but from its 60-minute exam (~25–40 total, ~1–2 in this domain), expect 1–1 from this objective — we provide 9 practice questions to prepare you well beyond it. (estimate)
9questions here
2free pages
4concepts
Questions 1–5
- 1
A multiclass classifier for traffic signs (stop, yield, speed limit) was evaluated. For the 'stop' class, the model correctly predicted 120 stops, but it also predicted 10 yields and 5 speed limits as stops. Additionally, 20 actual stops were predicted as yields and 10 actual stops were predicted as speed limits. What is the precision for the 'stop' class?
Select an answer first - 2
Given the confusion matrix below for a binary classifier, how many instances were correctly predicted by the model? | | Predicted Positive | Predicted Negative | |---|---|---| | Actual Positive | 80 | 20 | | Actual Negative | 10 | 90 |
Select an answer first - 3
In the confusion matrix below, what is the number of false negatives for the positive class? | | Predicted Positive | Predicted Negative | |---|---|---| | Actual Positive | 50 | 15 | | Actual Negative | 5 | 30 |
Select an answer first - 4
A binary classifier for email spam detection produced the following confusion matrix on a test set: TP=150, FP=10, FN=20, TN=820. The product manager wants a single metric that balances the trade-off between precision and recall, especially because the dataset is imbalanced. Which metric should be reported?
Select an answer first - 5
A multiclass classifier distinguishes between three animal classes: cat, dog, and bird. The confusion matrix shows that for the 'cat' class, the model correctly predicted 40 cats, but it also predicted 10 dogs as cats and 5 birds as cats. Additionally, 15 actual cats were predicted as dogs and 5 actual cats were predicted as birds. What is the precision for the 'cat' class?
Select an answer first
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