You produce a confidence interval estimate of a population mean from a simple random sample of size n.If sample size is doubled and the confidence requirement remains the same, the width of the new interval estimate will be half the width of the original.

Question

Quizplus · Accepted Answer

Doubling the sample size decreases the standard error of the mean (since it is inversely proportional to the square root of the sample size), but it does not halve the width of the confidence interval. The decrease in width is less than half because the width is also influenced by the critical value and the standard deviation, which are not affected by changes in sample size in the same way.

You Produce a Confidence Interval Estimate of a Population Mean