Sample A has a sample size of 15 and a standard deviation of 4.Sample B has a sample size of 30 and a standard deviation of 6.Both samples were taken from the same population.The 95 percent confidence interval estimate for the standard deviation of the population based on sample A will be ________ that based on sample B.
A)wider than
B)narrower than
C)the same in length as
D)None of the above.

Question

Quizplus · Accepted Answer

The confidence interval for the standard deviation of the population is inversely proportional to the square root of the sample size. Therefore, the confidence interval based on sample A will be narrower than that based on sample B because sample A has a smaller sample size.

Sample a Has a Sample Size of 15 and a Standard