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Chapter 10: Q. 83 (page 687)

Explain why it is not appropriate to perform a paired t test about the true mean difference (Outbound − Return) in flight times between Dubai and Doha. Note: See Exercise 94for an alternative approach to perform a significance test in this setting.

Short Answer

Expert verified

All the conditions are not satisfied since the large sample is not satisfied and it is therefore not appropriate to determine the confidence interval for the population mean difference.

Step by step solution

01

Step 1. Given information

The dots in the dot plot represents the difference between outbound and return in flight time.

02

Step 2. Explanation

To answer the question we must find out if the three conditions are satisfied or not, which is as:

Random: It is satisfied because the samples are independent random samples.

Independent: It is satisfied because the sample of days is less than of all population of all days.

Normal: It is not satisfied because the sample is not large and the distribution is not approximately Normal.

Thus, all the conditions are not satisfied since the large sample is not satisfied and it is therefore not appropriate to determine the confidence interval for the population mean difference.

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