ISTQB CT-AI
ML Metrics and Neural Networks
ML functional performance metrics
- Which four situations does a confusion matrix distinguish in a classification? Easy
- What does a false positive (FP) mean for a spam filter if "spam" is the positive class? Easy
- How is accuracy calculated? Easy
- How is precision calculated? Easy
- How is recall calculated? Easy
- Which other name is used for recall? Easy
- How is the F1-score defined? Easy
- A classifier yields TP = 40, TN = 50, FP = 5 and FN = 5. What is the accuracy? Easy
- A model has predicted 40 cases as positive, of which 30 are actually positive. What is the precision? Easy
- A test dataset contains 50 actually positive cases, of which the model identifies 45 as positive. What is the recall? Easy
- Why does a classification model rarely predict everything correctly all the time? Easy
Neural networks
- Which three main types of layers does a deep neural network have? Easy
- What can a single-layer perceptron be used for? Easy
- What are the neurons in the hidden layers also called? Easy
- What is an epoch when training a neural network? Easy
- How are the weights and bias values of a neural network typically initialized at the start of training? Easy
- Why are special coverage measures needed for neural networks? Easy
- What does neuron coverage measure? Easy
- What is the situation regarding commercial tools for neural network coverage measures? Easy
- What is the task of the output layer of a neural network? Easy
ML functional performance metrics
- A classifier yields TP = 80, FP = 20, FN = 40 and TN = 860. What are precision and recall? Medium
- A model achieves a precision of 80% and a recall of 60%. What is the F1-score (rounded)? Medium
- A classifier yields TP = 90, FP = 30, FN = 10 and TN = 70. Which values are correct? Medium
- Which question does precision answer? Medium
- What does a low F1-score mean? Medium
- A model for early cancer detection should miss as few actual cases of the disease as possible. Which metric is the priority? Medium
- A spam filter should sort out as few important emails as spam by mistake as possible. Which metric (spam = positive) is the priority? Medium
- What range of values applies to the F1-score? Medium
- A model yields TP = 45, FP = 5, FN = 15 and TN = 35. Which values are correct? Medium
- Which statement about the presentation of the confusion matrix is correct? Medium
- A model yields TP = 60, FP = 40, FN = 20 and TN = 880. What is the accuracy? Medium
Neural networks
- How does a neuron (after the input layer) calculate its activation value? Medium
- What happens during training with the error (loss) between the generated output and the known correct result? Medium
- Which statements about the bias of a neuron are correct? Medium
- How does a deep neural network process the input data on the way to the output? Medium
- How are fully connected networks and perceptrons related? Medium
- How does k-multisection neuron coverage (kMNC) work? Medium
- What does neuron boundary coverage (NBC) measure? Medium
- What are coverage measures for neural networks mainly used for? Medium
- Why is structural coverage alone not sufficient to assess a neural network? Medium
ML functional performance metrics
- Of 1,000 transactions, 10 are fraudulent. A model classifies all transactions as "no fraud" (fraud = positive). Which statements are correct? Hard
- A model yields TP = 8, FP = 2, FN = 2 and TN = 988 for 1,000 cases. Which values are correct? Hard
- Model A achieves precision 90% and recall 50%, model B precision 70% and recall 70%. Which model has the higher F1-score? Hard
- A model classifies all 1,000 cases as positive; 50 are actually positive. Which values result? Hard
- A model achieves a recall of 90%. The test dataset contains 200 actually positive cases. How many of them did the model miss? Hard
- A model has predicted 50 cases as positive and achieves a precision of 80%. How many false alarms (false positives) does this contain? Hard
- A confusion matrix is presented with swapped axes: row "actually positive": 70 predicted positive, 30 predicted negative; row "actually negative": 10 predicted positive, 890 predicted negative. Which values are correct? Hard
- In fraud detection, both missed fraud cases and false alarms are expensive. Which metric is suitable as a single summary criterion? Hard
- A model yields TP = 50, FP = 50, FN = 0 and TN = 900. Which values are correct? Hard
Neural networks
- Which logical function can a single-layer perceptron learn? Hard
- In which order do the steps of training a neural network take place? Hard
- Two otherwise identical networks differ only in their activation function. What follows from this? Hard
- Which statements about deep neural networks are correct? Hard
- A network has 200 neurons. During testing, the output of 150 neurons exceeds the specified threshold. What is the neuron coverage? Hard
- A network has 10 neurons whose output ranges are each divided into k = 4 sections. During testing, 28 sections are activated. What is the kMNC? Hard
- In a network with 50 neurons, the output of 5 neurons during testing lies outside the range observed in training (above the maximum or below the minimum). Which measure with which value results? Hard
- A test suite achieves 100% neuron coverage, yet the model fails in the field on slightly rotated images. Which explanations and consequences are there? Hard
- The test evaluation shows that a group of neurons in a hidden layer is never activated. How should a tester react? Hard
- A team wants to check whether its tests also cover behavior beyond the neuron outputs observed in training. Which coverage measure fits best? Hard
- A test manager wants to use classic statement and branch coverage as the main measure for a neural network. What speaks against this? Hard