13. An internal auditor is planning to use attribute sampling to test the effectiveness of a specific internal control related to approvals for cash disbursements. In attribute sampling, decreasing the estimated occurrence rate from 5% to 4% while keeping all other sample size planning factors exactly the same would result in a revised sample size that would be
A. Larger.
B. Smaller.
C. Unchanged.
D. Indeterminate.
ANSWER (B) is correct.
REQUIRED: The sample size effect of decreasing the estimated occurrence rate.
DISCUSSION: In an attribute test, the expected deviation rate is directly related to sample size. If it is decreased, sample size will decrease.
Answer (A) is incorrect. Increasing the expected error rate increases the sample size.
Answer (C) is incorrect. Changing one variable while holding all other factors constant changes the sample size.
Answer (D) is incorrect. Decreasing the expected error rate while holding all other factors constant decreases the sample size.