Elementary Statistics (12th Edition)

Published by Pearson
ISBN 10: 0321836960
ISBN 13: 978-0-32183-696-0

Chapter 13 - Nonparametric Statistics - 13-2 Sign Test - Basic Skills and Concepts: 13

Answer

there is a difference.

Work Step by Step

The sample size is more than 25, hence the value of the test statistic: $z=\frac{(x+0.5)-n/2}{\sqrt n/2}=\frac{(239+0.5)-291/2}{\sqrt{ 291}/2}=11.02.$ By using the table, the corresponding critical value: $z=\pm 2.575.$ If the value of the test statistic is in the rejection region, we reject the null hypothesis. 11.02 is more than 2.575 hence we reject the null hypothesis, hence there is a difference.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.