Refer to Exercise 12.12. Use the fitted regression model to answer the following questions. a….
Refer to Exercise 12.12. Use the fitted regression model to answer the following questions.
a. Can the hypothesis of no overall predictive value of the model be rejected at the the .01 level?
b. Test the hypothesis that distance to the hub airport is a significant predictor of revenue at the .05 level.
c. Place a 95% confidence interval of the slope associated with distance to the hub airport.
d. Test the hypothesis that the slope associated with population size is greater than .5 at the .05 level.
A regional airline transfers passengers from small airports to a larger regional hub airport. The airline’s data analyst was assigned to estimate the revenue (in thousands of dollars) generated by each of the 22 small airports based on two variables: the distance from each airport (in miles) to the hub and the population (in hundreds) of the cities in which each of the 22 airports is located. The data is given in the following table.
a. Produce three scatterplots: revenue versus distance, revenue versus population, and distance versus population.
b. For the 22 airports, is there a strong correlation between airport distance from the regional hub and city population?
c. Does there appear to a problem with high leverage points? Justify your answer.
d. Fit a first-order regression model relating revenue to distance and population size. Comment on the quality of the fit of the model to the data. e. Do the two estimated slopes appear to have the appropriate sign? If not, explain why.