* specify workspace
cd e:\DHS\DHS_data\scratch

use "...IAPR7EFL.DTA", clear 
keep hv001 hv002 hvidx hv024
gen cluster=hv001
gen hh=hv002
gen chline=hvidx
gen state=hv024
sort state cluster hh chline
save IAPR_temp.dta, replace 


use "...IAKR7EFL.DTA", clear 
keep v001 v002 b16 v024
keep if b16>0 & b16<.
gen cluster=v001
gen hh=v002
gen chline=b16
gen state=v024
sort state cluster hh chline

* At this point a merge will fail, because of a few duplicated values of b16 in the KR file. 
* Identify the duplicates.
egen repeated_b16=seq(),by(cluster hh chline)
tab repeated_b16

* There are 7 households in which the same value of b16 appears twice
* Remove the second case in duplicates. Note: it is possible that in some households it is the
*   first, not the second, that should be removed. Values of b16 could be edited.
list if repeated_b16>1, table clean
drop if repeated_b16>1
drop repeated_b16

* sort again
sort state cluster hh chline
* Note that this is a 1:1 merge
merge 1:1 state cluster hh chline using IAPR_temp.dta
tab _merge

* There is one case with _merge=1. This is a child in the KR file with a valid value of b16 but
*  the value does not appear in the PR file. Should not happen; drop this case but could edit b16.
list if _merge==1, table clean
drop if _merge==1