Question

The following data are the monthly salaries y and the grade point averages x for students who obtained a bachelor's degree in business administration. GPA Monthly Salary ($) 2.7 3,600 3.4 3,800 3.7 4,200 3.1 3,800 3.5 4,200 2.8 2,300 The estimated regression equation for these data is = -430 + 1,275x and MSE =293,625. a. Develop a point estimate of the starting salary for a student with a GPA of 3.0 (to 1 decimal). $ b. Develop a 95% confidence interval for the mean starting salary for all students with a 3.0 GPA (to 2 decimals). $ ( , ) c. Develop a 95% prediction interval for Ryan Dailey, a student with a GPA of 3.0 (to 2 decimals). $ ( , )

Answer 1

Y= -430+1275*X

MSE= 293625

a) X= 3

Y= -430+1275*3= 3395

b) 95% confidence interval: t(0.05/2, n-2)

t-critical: t(0.05/2, 4)= 2.776445

n=6

X0= 3.0

c) 95% Prediction interval:

Y= -430+1275*X

t-critical: t(0.05/2, 4)= 2.776445

n=6

X0= 3.0