Question: a. Regress (Y) education on Age (X2) only. State the fitted simple regression function.

Hint: Since you want to compare this result to the multiple regression result, you want to include Female (X1) and Sibsnew (X3) in the regression statement (e.g. regression var=educ age femalesibsnew/statistics=....) even though you don’t include these variables in the equation. Otherwise, you end up having different numbers of cases.

b. Compare this b2 to b2 obtained in 6.101.d. How would you explain the difference?

c. Does SSR(X2) equal SSR(X2|X1,X3) here? If not, is the difference substantial?

d. Refer to the correlation matrix in 6.101.d. Briefly comment on the inclusion of which variable brought the change in b2, Female or Siblings?