The following regression equation was calculated for a class of 24 CPA II students.
Ŷ = 3.1 + 0.021X1
+ 0.075X2
+ 0.043X3
Standard error (0.019) (0.034) (0.018)
Where: Y = Students score on a theory examination

X1
= Students rank (from the bottom) in high school
X2
= Students verbal aptitude score
X3
= a measure of the students character.
Required:
(a) Calculate the t ratio and the 95% confidence interval for each regression
coefficient.
(8 marks)
(b) What assumptions did you make in (a) above? How reasonable are they? (4
marks)
(c) Which regressor gives the strongest evidence of being statistically discernible?
(2 marks)
(d) In writing up a final report, should one keep the first regressor in the equation,
or drop it? Why? (6 marks)