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*** Pooled CS ***
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use "C:\Users\royj\Dropbox\eco5720\Data Sets- STATA\FERTIL1.DTA", clear
reg kids y74 y76 y78 y80 y82 y84 educ age

use "C:\Users\royj\Dropbox\eco5720\Data Sets- STATA\CPS78_85.DTA", clear
reg lwage y85 educ y85educ

use "C:\Users\royj\Dropbox\eco5720\Data Sets- STATA\KIELMC.DTA", clear

su rprice if year==1978 & nearinc==0
g mfr78=`r(mean)'
su rprice if year==1981 & nearinc==0
g mfr81=`r(mean)'
g d1 = mfr81 - mfr78
su d1
di "Effect of time for homes far from incin. = " `r(mean)'
reg rprice y81 if nearinc==0

su rprice if year==1978 & nearinc==1
g mnr78=`r(mean)'
su rprice if year==1981 & nearinc==1
g mnr81=`r(mean)'
g d2 = mnr81 - mnr78
su d2
di "Effect of time for homes near incin. = " `r(mean)'
reg rprice y81 if nearinc==1

g did = d2 - d1
su did
di "DID estimate = " `r(mean)'
reg rprice y81 nearinc y81nrinc

keep year near mfr78 mfr81 mnr78 mnr81

duplicates drop year nearinc, force

g arprice=.
replace arprice=mfr78 if year==1978 & nearinc==0
replace arprice=mfr81 if year==1981 & nearinc==0
replace arprice=mnr78 if year==1978 & nearinc==1
replace arprice=mnr81 if year==1981 & nearinc==1

drop mfr78 mfr81 mnr78 mnr81
expand 2
replace year=1979 if _n==5 | _n==6
replace year=1980 if _n==7 | _n==8
sort year nearinc

twoway (scatter arprice year if nearinc==0 & year!=1979 & year!=1980, xline(1980) ytitle("Average Price") legend(lab(1 "Far from Inc.")) mcolor(blue) sort) ///
(scatter arprice year if nearinc==1 & year!=1979 & year!=1980, mcolor(maroon) legend(lab(2 "Near Inc.")) sort msymbol(diamond)) ///
(function y = 63692.86, range(1978 1980) lc(maroon) legend(lab(3 "Near Inc. Before Inc."))) ///
(function y = 70619.24, range(1980 1981) lc(maroon) legend(lab(4 "Near Inc. After Inc."))) ///
(function y = 82483.13, range(1980 1981) lc(maroon) lp(dash) legend(lab(5 "Near Inc. After Inc. Only Time"))) ///
(function y= 82517.23, range(1978 1980) lc(blue) legend(lab(6 "Far from Inc. Before Inc."))) ///
(function y = 101307.5, range(1980 1981) lc(blue) legend(lab(7 "Far from Inc. After Inc.")))