If a confidence interval for a population mean is found to be wider than desired,the next step should be to ________.
A)go ahead and use the confidence interval anyway
B)take another sample of the same size as the original and use the standard deviation of the combined data for the confidence interval
C)change the confidence level to a smaller value
D)calculate the appropriate sample size using the standard deviation from the first sample and take a sample of that size in order to reduce the standard error

Question

Quizplus · Accepted Answer

The width of a confidence interval is determined by the standard error, which is affected by sample size. Therefore, to decrease the width of a confidence interval, one can increase the sample size. In this scenario, calculating the appropriate sample size using the standard deviation from the first sample and taking a sample of that size in order to reduce the standard error would be the best option.

If a Confidence Interval for a Population Mean Is Found