The following equations were estimated using the data in ECONMATH. The first equation is for men and the second is for women. The third and fourth equations combine men and women.

score 5 20.52 1 13 .60 colgpa 1 0 .670 act 13.722 10.942 10.1502 n 5 406. R2 5 .4025, SSR 5 38,781.38.

score 5 13 .79 1 11 .89 colgpa 1 1 .03 act 14.112 11.092 10.182 n 5 408, R2 5 .3666, SSR 5 48,029.82.

score 5 15.60 1 3.17 male 1 12.82 colgpa 1 0.838 act 12.802 10.732 10.722 10.1162 n 5 814, R2 5 .3946, SSR 5 87,128.96.

score 5 13.79 1 6 .73 male 1 11 .89 colgpa 1 1 .03 act 1 1 .72 male ? colgpa 2 0 .364 male ? act 13.912 15.552 11.042 10.172 11.442 10.2322 n 5 814, R2 5 .3968, SSR 5 86,811.20.

(i) Compute the usual Chow statistic for testing the null hypothesis that the regression equations are the same for men and women. Find the p-value of the test.

(ii) Compute the usual Chow statistic for testing the null hypothesis that the slope coefficients are the same for men and women, and report the p-value.

(iii) Do you have enough information to compute heteroskedasticity-robust versions of the tests in

(ii) and (iii)? Explain.