Re: Synthetic Control Method (Abadie et al. 2010)

Link to the paper here.

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      name:  <Solomon Negash>
       log:  ~\myReplications\synthetic-control\synthdid.smcl
  log type:  smcl
 opened on:  16 Dec 2018, 18:24:07

 // Replication of Synthetic Control method - the last graphs 4-7

 //1.1. Load dataset, tsset and loop through all units and store the results of synth using the keep option.

. sysuse smoking, clear
(Tobacco Sales in 39 US States)

. tsset state year
       panel variable:  state (strongly balanced)
        time variable:  year, 1970 to 2000
                delta:  1 unit

. forval i=1/39{
  . qui synth cigsale retprice cigsale(1988) cigsale(1980) cigsale(1975), ///
> xperiod(1980(1)1988) trunit(`i') trperiod(1989) keep(synth_`i', replace)
  . }

 //2.  Quitely loop through all saved datasets and create the relevant variables (years and treatment effects). Drop missing observations.

. qui forval i=1/39{
. use synth_`i', clear
. rename _time years
. gen tr_effect_`i' = _Y_treated - _Y_synthetic
. keep years tr_effect_`i'
. drop if missing(years)
. save synth_`i', replace
. }

 //3. Load the first dataset from step 2 and merge with the rest of datasets.

. use synth_1, clear
(Tobacco Sales in 39 US States)

. forval i=2/39{
  . qui merge 1:1 year using synth_`i', nogenerate
  . label var tr_effect_`i' "tr_effect_`i'" 
  . }

// Rename tr_effect_i to tte_j by ranking based on MSPE scores. 

. qui rename tr_effect_17 tte_1
.	(...)

//4. Plot 

//Figure 4 (38 control states)

. set scheme s1mono 
. local lp
. forval i=1/38 {
  .  local lp `lp' line tte_`i' years, lcolor(gs12) || }
.  twoway `lp' || line tte_3 years, lcolor(black) lwidth(medium) text(-40 1984 "Passage of Proposition 99 --->", size(*0.75)) ///
>   legend(off) yline(0, lcolor(black) lwidth(thick) lpattern(dash)) xline(1989, lwidth(medium) lpattern(dash)) ///
>   caption(Re: Figure 4. Per-cap cig sales gaps in California & placebo gaps in 38 control states.)

. graph export synth38.png, replace
(file synth38.png written in PNG format)
// <image src="synth38.png" width="358" height="300"


//Figure 5 (34 control states)

. drop tte_35 tte_36 tte_37 tte_38 tte_39 
. local lp
. forval i=1/34 {
  .    local lp `lp' line tte_`i' years, lcolor(gs12) || 
  . }
. twoway `lp' || line tte_3 years, lcolor(black) lwidth(medium) text(-40 1984 "Passage of Proposition 99 --->", size(*0.75)) ///
>   legend(off) yline(0, lcolor(black) lwidth(thick) lpattern(dash)) xline(1989, lwidth(medium) lpattern(dash)) ///
>   caption(Re: Figure 5. Per-cap cig sales gaps in California & placebo gaps in 34 control states)

. graph export synth34.png, replace
(file synth34.png written in PNG format)
 // <image src="synth34.png" width="358" height="300">


//Figure 6 (29 control states)

. drop tte_30 tte_31 tte_32 tte_33 tte_34
. local lp
. forval i=1/29 {
  .    local lp `lp' line tte_`i' years, lcolor(gs12) || 
  . }
. twoway `lp' || line tte_3 years, lcolor(black) lwidth(medium) text(-40 1984 "Passage of Proposition 99 --->", size(*0.75)) ///
>   legend(off) yline(0, lcolor(black) lwidth(thick) lpattern(dash)) xline(1989, lwidth(medium) lpattern(dash)) ///
>   caption(Re: Figure 6. Per-cap cig sales gaps in California & placebo gaps in 29 control states)
. graph export synth30.png, replace
(file synth30.png written in PNG format)
 // <image src="synth30.png" width="358" height="300">


 


  

//Figure 7 (19 control states)

. drop tte_20 tte_21 tte_22 tte_25 tte_23 tte_24 tte_26 tte_27 tte_28
. local lp
. forval i=1/19 {
  .    local lp `lp' line tte_`i' years, lcolor(gs12) || 
  . }
. twoway `lp' || line tte_3 years, lcolor(black) lwidth(medium) text(-40 1984 "Passage of Proposition 99 --->", size(*0.75)) ///
>   legend(off) yline(0, lcolor(black) lwidth(thick) lpattern(dash)) xline(1989, lwidth(medium) lpattern(dash)) ///
>   caption(Re: Figure 7. Per-cap cig sales gaps in California & placebo gaps in 19 control states)
. graph export synth19.png, replace
(file synth19.png written in PNG format)
 // <image src="synth19.png" width="358" height="300">


. log close 
      name:  <Solomon Negash>
       log:  ~\myReplications\synthetic-control\synthdid.smcl
  log type:  smcl
 closed on:  16 Dec 2018, 18:24:21
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