set more off
set maxvar 10000

cd e:\DHS\DHS_data\IR_files

use MWIR41FL.dta, clear
gen survey=1
append using MWIR4DFL.dta
replace survey=2 if survey==.
append using MWIR61FL.dta
replace survey=3 if survey==.

* The strata in MW41 are given by s006
* The strata in MW4D are given by group(sdist v025)
* The strata in MW61 are given by v022

gen mw_00_strata = s006
egen mw_04_strata = group(sdist v025), label
gen mw_10_strata = v022

gen strata_temp=.
replace strata_temp=mw_00_strata if survey==1
replace strata_temp=mw_04_strata if survey==2
replace strata_temp=mw_10_strata if survey==3

egen strata=group(survey strata_temp)

tab strata survey, table clean