Question 271 of 1,000
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Matching Evaluation Metrics to Use Cases

This PMLE practice question tests your understanding of pmle exam topics. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.

Match each model evaluation metric to its use case.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

Accuracy: Correct when classes are balanced and errors have equal cost

Accuracy is correctly matched with balanced classes and equal error cost; Precision with minimizing false positives; Recall with minimizing false negatives; F1 Score with balancing precision and recall for imbalanced classes. Option E incorrectly pairs Accuracy with 'when false positives are costly' which is actually the domain of Precision. The main trap is confusing accuracy with precision when dealing with asymmetric costs.

Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

  • Accuracy: Correct when classes are balanced and errors have equal cost

    Why this is correct

    Accuracy measures overall correctness, suitable when class distribution is balanced and cost of false positives and false negatives is similar.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Precision: When false positives are costly (e.g., spam detection)

    Why this is correct

    Precision focuses on minimizing false positives, important in scenarios like spam detection where legitimate emails should not be flagged as spam.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Recall: When false negatives are costly (e.g., medical diagnosis)

    Why this is correct

    Recall emphasizes capturing all positive instances, critical in medical diagnosis to avoid missing a disease.

    Related concept

    Read the scenario before looking for a memorised answer.

  • F1 Score: When needing balance between precision and recall, especially imbalanced classes

    Why this is correct

    F1 Score is the harmonic mean of precision and recall, useful for imbalanced datasets where both false positives and false negatives are important.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Accuracy: When false positives are costly

    Why it's wrong here

    Incorrect — this describes precision, not accuracy. Accuracy does not specifically address the cost of false positives.

Common exam traps

Common exam trap: answer the scenario, not the keyword

Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.

Detailed technical explanation

How to think about this question

This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.

KKey Concepts to Remember

  • Read the scenario before looking for a memorised answer.
  • Find the constraint that changes the correct option.
  • Eliminate answers that are true in general but not in this case.
  • Use explanations to understand the rule behind the answer.

TExam Day Tips

  • Underline the problem statement mentally.
  • Watch for words such as best, first, most likely and least administrative effort.
  • Review why wrong options are wrong, not only why the correct option is correct.

Key takeaway

Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.

Real-world example

How this comes up in practice

A startup's cloud architect reviews their monthly bill and notices costs are higher than expected for a long-running batch job. Switching from on-demand instances to Reserved Instances — or using Spot/Preemptible VMs — can reduce compute costs by up to 72 %. Questions like this test whether you understand the tradeoffs between commitment, flexibility, and cost across cloud pricing models.

Quick reference

Asymmetric Encryption Algorithm Comparison

AlgorithmKey ExchangeSignaturesEquivalent Security KeyNotes
RSA-3072YesYes128-bitWidely deployed; slow for bulk data
ECDSA P-256NoYes128-bitFast signatures; standard TLS certs
ECDH / ECDHEYesNo128-bitPerfect forward secrecy in TLS 1.3
DH / DHEYesNo128-bit (3072-bit key)Replaced by ECDHE in modern TLS
Ed25519NoYes~128-bitSSH keys, modern PKI

What to study next

Got this wrong? Here's your next step.

Identify which PMLE exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.

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FAQ

Questions learners often ask

What does this PMLE question test?

Read the scenario before looking for a memorised answer.

What is the correct answer to this question?

The correct answer is: Accuracy: Correct when classes are balanced and errors have equal cost — Accuracy is correctly matched with balanced classes and equal error cost; Precision with minimizing false positives; Recall with minimizing false negatives; F1 Score with balancing precision and recall for imbalanced classes. Option E incorrectly pairs Accuracy with 'when false positives are costly' which is actually the domain of Precision. The main trap is confusing accuracy with precision when dealing with asymmetric costs.

What should I do if I get this PMLE question wrong?

Identify which PMLE exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.

What is the key concept behind this question?

Read the scenario before looking for a memorised answer.

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Last reviewed: Jun 11, 2026

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This PMLE practice question is part of Courseiva's free Google Cloud certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PMLE exam.