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a program for ADF test with two dummy variables

Posted: Fri Jul 15, 2016 2:15 am
by eisamabodian
I want to simulate this ADF unit root test with two dummy variables in intercept and trend.

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dy=c(1)+C(2)*DU1+c(3)*DU2+C(4)*DUT1+C(5)*DUT2+C(6)*T+C(7)*Y(-1)+C(7)*DY(-1)
Does anybody can help me.My original model has two dummy variables.
And 219 observations.

DU1=structural break is in 153th observation
DU2=structural break is in 173th observation

for example a simulation program with 20000 replications.
I must calculate critical values at 1%,5% and 10% significance level.
i wrote this program to this end with 10000 observations and 10000 replications.

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wfcreate u 1 10000 rndseed 12345 series tau_statistic1 series tau_statistic2 series tau_statistic3 series dum2=@recode(@date>=@dateval(" 6941 "),1,0) "6941 is structural break date series dum5=@recode(@date>=@dateval(" 7900 "),1,0) "7900 is structural break date series dumt2=dum2*@trend series dumt5=dum5*@trend for !i=1 to 10000 smpl @first @first series y=0 smpl @first+1 @last series y=y(-1)+nrnd series dy=y-y(-1) equation equ1.ls dy c y(-1) dum2 dum5 dy(-1) dy(-2) dy(-3) dumt2 dumt5 @trend tau_statistic1(!i)=equ1.@tstats(2) equation equ2.ls dy c y(-1) dum2 dum5 dy(-1) dy(-2) dy(-3) dumt2 dumt5 tau_statistic2(!i)=equ2.@tstats(2) equation equ3.ls dy dum2 y(-1) dum5 dy(-1) dy(-2) dy(-3) dumt2 dumt5 tau_statistic3(!i)=equ3.@tstats(2) next smpl @first @last scalar k1=@quantile(tau_statistic1,0.01) scalar k2=@quantile(tau_statistic1,0.05) scalar k3=@quantile(tau_statistic1,0.1) scalar k4=@quantile(tau_statistic2,0.01) scalar k5=@quantile(tau_statistic2,0.05) scalar k6=@quantile(tau_statistic2,0.1) scalar k7=@quantile(tau_statistic3,0.01) scalar k8=@quantile(tau_statistic3,0.05) scalar k9=@quantile(tau_statistic3,0.1) table(5,5) zzzz zzzz(1,2)="none" zzzz(1,3)="intercept" zzzz(1,4)="intercept & trend" zzzz(2,1)="1%" zzzz(3,1)="5%" zzzz(4,1)="10%" zzzz(2,4)=k1 zzzz(3,4)=k2 zzzz(4,4)=k3 zzzz(2,3)=k4 zzzz(3,3)=k5 zzzz(4,3)=k6 zzzz(2,2)=k7 zzzz(3,2)=k8 zzzz(4,2)=k9

Now i want to run this program with 10000 replications and 219 observations.
please guide.