clear
use "/Users/kaewkwan_katie/Documents/EE325_2019/DATA/table7.11.dta"
/*question1*/
/*Example Restricted Least Squares: Testing Linear Equality Restrictions*/

gen lnoutput = log(output)
gen lncapital = log(capital)
gen lnlabor = log(labor)
reg lnoutput lncapital lnlabor

global xlist lncapital lnlabor 
reg lnoutput $xlist

gen outputlabor = output/labor
gen lnoutputlabor = log(outputlabor)
gen lnclratio = log(clratio)
bro
reg lnoutputlabor lnclratio

clear
use "/Users/kaewkwan_katie/Documents/EE325_2019/DATA/table9.1.dta"

/*question2*/

reg salary d2 d3


clear
use "/Users/kaewkwan_katie/Documents/EE325_2019/DATA/table9.4.dta"

/*question3a*/

gen d1=0
replace d1=1 if d2==0&d3==0&d4==0
bro

/*Without intercept term*/
reg frig d1 d2 d3 d4
reg frig d1 d2 d3 d4, nocon

/*question3b*/


reg frig d2 d3 d4


clear
use "/Users/kaewkwan_katie/Documents/EE325_2019/DATA/table8.9.dta"

/*question 4*/
/*Chow test*/
reg savings income if year<1982
reg savings income if year>1981
reg savings income

/*The Dummy Variable Alternative to the Chow test*/
gen d =0
replace d=1 if year>1981
gen dx =income*d

reg savings d income dx


/*Multicollinearity*/
clear
use C:\Users\Sony\Documents\EE325_2_2012\STATA\table10.5.dta 

/*question 5*/

reg y x2 x3
reg y x2
reg y x3