Answer to Question #92346 in Statistics and Probability for DESMOND

Question

JoKO aims to construct a confidence interval for the mean of a normal population with known standard deviation. List three factors that could help her in reducing the size of the margin error. Then, she collects a random sample of size from a population and from the data collected she compute a 95% confidence interval for the mean of the population. Based on the same dataset, state one factor that could produce a new confidence interval with a larger width (Hint: Larger margin of error)

Answer 1

Three factors that could help her in reducing the size of the margin error:

1. Increasing the sample size.
2. Lowering the confidence level.
3. Using a one-sided confidence interval

The factor that could produce a new confidence interval with a larger width - increasing the confidence

level from 95% to 99%.