You have been given the following data (available on the online platform in either file CSE21.xlsx or CSE22.sav).
a. Plot the scatter diagrams and find the correlation coefficients between the four variables. Which of the three independent variables are likely to explain the variation in Y?
b. Build all possible regression models (there are seven) and for each one note whether the independent variables are significant, the coefficient of determination and the standard error of the regression.
c. Of the seven models developed in (b) which would you use to estimate Y?
d. For your chosen model investigate the standardized residuals to determine whether they are normally distributed and have constant variance.