We have calculated a 95% confidence interval and would like our next confidence interval to have a smaller margin of error without losing any confidence. In order to do
This, we can
I. change the z∗ value to a smaller number.
II. take a larger sample.
III. take a smaller sample.
A) I only
B) II only
C) III only
D) I and II
E) I and III

Question

Quizplus · Accepted Answer

To reduce the margin of error in a confidence interval without losing confidence, taking a larger sample size is effective. Changing the z* value to a smaller number would actually decrease the confidence level, and taking a smaller sample would increase the margin of error.

We Have Calculated a 95% Confidence Interval and Would Like