use "L:\Alma Kudebayeva\Fall2017\ECN5012 Econometrics\Chapter7\eaef22.dta", clear *****EX7.3 ************** *****Goldfed-Quandt test twoway (scatter EARNINGS S) su EARNINGS S sort S reg EARNINGS S EXP MALE reg EARNINGS S EXP MALE in 1/203 sort S reg EARNINGS S EXP MALE in 338/540 ****Ex7.4**********White test**** reg EARNINGS S EXP MALE predict EEARN, resid g EEARNSQ=EEARN*EEARN gen SSQ=S*S gen EXPSQ=EXP*EXP gen MALESQ=MALE*MALE g SEXP=S*EXP g MALEEXP=MALE*EXP g MALES=MALE*S reg EEARNSQ S EXP MALE SSQ EXPSQ MALESQ SEXP MALES MALEEXP *************************************************************** ******Ex7.5**** the data for the cost // use "L:\Alma Kudebayeva\Fall2017\ECN5012 Econometrics\Chapter7\schools.dta", clear twoway (scatter COST N if OCC==1, sort) (scatter COST N if REGULAR==1, sort) reg COST N reg COST OCC N NOCC sort N reg COST N in 1/26 sort N reg COST N in 49/74 sort N reg COST OCC N NOCC in 1/26 reg COST OCC N NOCC in 49/74 twoway (scatter COST N) if OCC==1 twoway (scatter COST N) if REGULAR==1 ********Ex7.6************************************************ use "L:\Alma Kudebayeva\ECN5012Econometrics _Fall2015\Chapter7\educ(1).dta", clear sort GDP reg EDUC GDP in 1/14 sort GDP reg EDUC GDP in 25/38 ************7.8***************************************** use "L:\Alma Kudebayeva\Spring 2020\ECN3184 Econometric Methods\Chapter7\eaef22.dta",clear gen LGEARN=ln(EARNINGS) twoway (scatter LGEARN S) sort S reg LGEARN S EXP MALE in 1/203 sort S reg LGEARN S EXP MALE in 338/540 *******White test****************** reg LGEARN S EXP MALE predict ELGEARN, resid g ELGEARN2=ELGEARN*ELGEARN gen SSQ=S*S gen EXPSQ=EXP*EXP gen MALESQ=MALE*MALE g SEXP=S*EXP g MALEEXP=MALE*EXP g MALES=MALE*S reg ELGEARN2 S EXP MALE SSQ EXPSQ SEXP MALEEXP MALES reg EARNINGS S EXP MALE reg EARNINGS S EXP MALE, robust reg LGEARN S EXP MALE reg LGEARN S EXP MALE, robust reg EARNINGS S EXP MALE estat hettest reg LGEARN S EXP MALE estat hettest