Question

The administrators at the University of Oklahoma wonder if Oklahoma residents or non-Oklahoma residents differ in their excitement to go home for the holidays following final exams. They randomly select 100 Oklahoma residents and 100 non-Oklahoma residents for their study. They then ask all participants to rate their excitement level on a scale of 1-10. The mean excitement level for Oklahoma residents was 7.745, while the mean excitement level for non-Oklahoma residents was 7. They create the following 95% confidence interval for the mean difference: -1.78 to 3.27. Which of the following is the best way to interpret their results based on their confidence interval?
a. The administrators are 95% confident that Oklahoma residents are significantly more excited than non-Oklahoma residents to go home for the holidays.
b. The administrators are 95% confident that Oklahoma residents are significantly less excited than non-Oklahoma residents to go home for the holidays.
c. The administrators are 95% confident that Oklahoma residents significantly differ from non-Oklahoma residents in their excitement to go home for the holidays because their interval covers 0.
d. The administrators are unable to tell if there is a true difference between Oklahoma and non-Oklahoma residents in their excitement to go home for the holidays because their interval covers 0.

Answer 1

Answer:

d. The administrators are unable to tell if there is a true difference between Oklahoma and non-Oklahoma residents in their excitement to go home for the holidays because their interval covers 0.

Step-by-step explanation:

The confidence interval refers to a rabje of statistically calculated values used in establishing a certain level of confidence in the outcome of a data.

The confidence interval is calculated thus :

Mean ± (Zcritical * Error)

The ± sign ensures we have the lower and upper boundary of our confidence level.

From the confidence level given in the question : -1.78 to 3.27

Since 0 is contained in the confidence interval range given, then it can be concluded that the difference in excitement between Oklahoma and non oklahoma residents cannot be adequately established.