A study was done to predict GPA on the basis of Facebook log

A study was done to predict GPA on the basis of Facebook logins. The regression equation is: y(hat) =-0.25x+4.09

(a) What is the meaning of the intercept and the slope, in this context?

(b) Nada logs in twice more per day than Yara. Compare the predicted GPA for these 2 students.

(c) Omar logs in 4 times per day and has a GPA of 3.2. What is the residual (error) for Omar?

Solution

a)

when you dont have any facebook logins you will have a GPA of 4.09

b)

Y = -0.25 * 2 + 4.09 = 3.59

c)

Y = -0.25 * 4 + 4.09 = 3.09

residual = 3.09 - 3.2 = -0.11