Attribute Sampling Sample Size Factors

Audit Sampling
Answer Correct answer: A — Decreasing the tolerable error rate increases the sample size.

When utilizing attribute sampling, which of the following would cause the sample size to increase?

  1. Tolerable error rate decrease Correct Answer
  2. Expected error rate decrease
  3. Population size decrease
  4. Acceptable risk level increase

Community Votes

A
75%
B
25%

75% of anonymous learners picked answer A. Votes are pick records left by other test-takers — they are not the verified answer.

Community Insight

The question tests the inverse relationship between tolerable error rate and sample size, a common trap for those confusing it with expected error rate.

In attribute sampling, a decrease in the tolerable error rate requires a larger sample size to ensure the audit objective is met with higher precision, as confirmed by community consensus.

Choosing B (Expected error rate decrease) is common because users confuse the direct relationship of expected error with the inverse relationship of tolerable error.

Community Discussion (3 comments)

MJORGER 👍 1 Selected: A
A. Tolerable error rate decrease When the tolerable error rate decreases, the sample size needs to increase in order to provide a more precise estimate.
marc4354345 👍 2 Selected: A
If fewer errors are tolerated, then the sample size must be increased to increase certainty.
Rachy 👍 1 Selected: B
B. Expected error rate

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Expert Analysis

Why the Answer Is Correct

A lower tolerable error rate means the auditor is less willing to accept errors. To prove that the error rate is indeed below this stricter threshold, more evidence is needed, necessitating a larger sample size. This aligns with the inverse relationship defined in audit sampling formulas.

Why the Other Options Are Wrong

Option B is incorrect because a decrease in the expected error rate actually leads to a smaller sample size (direct relationship). Option C is incorrect because population size rarely impacts sample size significantly unless the population is very small. Option D is incorrect because increasing the acceptable risk level (lower confidence) allows for a smaller sample size.

Community Comment Notes

Community comments strongly validate Option A, noting that fewer tolerated errors demand increased certainty. There is a minority vote for Option B, likely due to confusing tolerable error with expected error, but the logic for A is sound.

Official Reference

Exam Strategy

Remember the mnemonic 'T-E-R-R': Tolerable (Inverse), Expected (Direct), Risk (Inverse), Population (None). This helps quickly determine the relationship without deriving the formula.

Related Analysis

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