Which combination of factors would definitely increase the width of a confidence interval?
A)Increase the sample mean and increase the sample size
B)Decrease the sample mean and increase the sample size
C)Increase the sample mean and increase the percentage of confidence
D)Decrease the sample mean and decrease the percentage of confidence

Question

Quizplus · Accepted Answer

Increasing the percentage of confidence (e.g., from 95% to 99%) requires a wider interval to capture the population parameter with higher certainty, thus increasing the width of the confidence interval. Changes in the sample mean do not affect the width of the confidence interval, and increasing the sample size actually decreases the width of the confidence interval, making options A, B, and D incorrect in the context of definitely increasing the width.

Which Combination of Factors Would Definitely Increase the Width of a Confidence