Did the estimated regression equation provide a good fit Sup

Did the estimated regression equation provide a good fit? Suppose you where the president of South University. After reviewing the results, would you have any concerns about the performance of your university as compared to other online universities? Suppose you were president of the University of Phoenix. After reviewing the results, would you have any concerns about the performance of your university as compared to other online universities?

Solution

A) ANNUAL MAINTENACE = 10.5279568755945 + (0.95344043969982 * WEAKLY USAGE)

B) SINCE P-VALUE < 0.05..THE TEST IS NOT SIGNIFICANT...

C) WEAKLY USAGE = 30.. T-SCORE FOR DF (10-2) =8 AND ALPHA = 0.05 IS = 2.306004...

standard error of weekly usage = 0.138159709382233.....
confidence interval for weekly usage = 30 + or - ( 0.138159709382233*2.306004)... = [ 29.6814 , 30.3186 ]

now, Annual maintenance when weekly usage = 30.3186 is...= 39.435..
and when weekly usage = 29.6814... annual maintenance = 38.827...
confidence interval for annual maintenance when weekly usage is 30 = [ 38.827 , 39.435 ]...

d) maintenace contract = 3000$ i.e, 30 in hundred of dollars..

30 = a + b*(weekly usage)..

we know a and b..so, usage = (30-a) / b = 20.42293..

mean of weekly usage recored here is = 25.3....

but for a maintenance cost $3000, the ideal weekly usage should be 20.42293..

so, as the mean weekly usage is more than that , it is likely to cost more than $3000..so, I would not recommend purchasing it,