Assign group ID based on variable

[Yifei Liu]

Dear Statalist,

I have a data set with two variables 'id' and 'group'. I want to assign observations with a same 'group id' if their 'group' variables are overlapping.

In the example data below, ideally, I want all four observations receive a same 'group id'. I tried splitting out the 'group' variables and then re-arranged the data but could not manage to get what I want.

* Example generated by -dataex-. For more info, type help dataex
clear
input str16 id str487 group
"A" "A,B,C"
"B" "A,C,D"
"C" "B,C,D"
"D" "C,D"  
end

Any suggestions are appreciated.

Thanks!

[Øyvind Snilsberg]

how would you group the following ids,

* Example generated by -dataex-. For more info, type help dataex
clear
input byte id str3 group
1 "A"  
2 "A,B"
3 "B"  
end

[Yifei Liu]

how would you group the following ids,

* Example generated by -dataex-. For more info, type help dataex
clear
input byte id str3 group
1 "A"
2 "A,B"
3 "B"
end

I would like to assign them the same group id as well.