This table gives further details of the multiple regression estimated in Exercise 31. Assume that the MRM satisfies the conditions for using this model for inference.
(a) Fill in the
-statistics.
(b) Estimate the
-values using the Empirical Rule. Only rough estimates are needed.
(c) Does the addition of Distance to a simple regression using only population as an explanatory variable produce a statistically significant increase in
?
(d) If the populations of a city were to grow by 10,000, on average what effect would this growth have on revenue? Give a range, rounded to presentation precision.
Exercise 31
An airline developed a regression model to predict revenue from flights that connect “feeder” cities to its hub airport. The response in the model is the revenue generated by flights operating to the feeder cities (in thousands of dollars per month), and the two explanatory variables are the air distance between the hub and the feeder city (Distance, in miles) and the population of the feeder city (in thousands). The least squares regression equation based on data for 37 feeder locations last month is
(a) The airline plans to expand its operations to add an additional feeder city. One possible city has population 100,000 and is 250 miles from the hub. A second possible city has population 75,000 and is 200 miles from the hub. Which would you recommend if the airline wants to increase total revenue?
(b) What is the interpretation of the intercept in this equation?
(c) What is the interpretation of the partial slope for Distance?
(d) What is the interpretation of the partial slope for Population?