Help create a person ID for panel data

[Zarah Jimenez]

Dear Statalisters,

I would like to ask for advice regarding creating person ID variables from a household survey panel data.

I have appended together 3 years of household survey data to construct a panel for use in my masters thesis. The datasets share a common household identifier (zzhhid), but none for individuals. There is a variable for respondent line number (lno) for each household member, but further checking showed that the lc101_lno_ can change year from year since members may move in/out of the household.

I attach below a sample of the dataset to better illustrate my problem. I have sorted out the dataset using below command just to preview which observations makes sense to use for the panel. The sorting isnt perfect as you can see, but it allows me to check at least whether which observations make sense, given the lack of an personID variable. Hope you can advise me on how I can construct a person ID variable in this case. Thank you in advance!

gsort zzhhid rel lno age sex -year

* Example generated by -dataex-. To install: ssc install dataex
clear
input str18 zzhhid float year byte(lno rel sex age marstat educ)
"1010A2226" 2003 1 1 2 68 3 2
"1010A2226" 2006 1 1 2 72 3 1
"1010A2226" 2009 1 1 2 75 3 1
"1010A2226" 2009 2 3 1 35 2 5
"1010A2226" 2009 4 5 2 37 2 4
"1010A2332" 2003 1 1 1 68 2 1
"1010A2332" 2006 1 1 1 72 2 1
"1010A2332" 2009 1 1 1 74 2 2
"1010A2332" 2003 2 2 2 63 2 2
"1010A2332" 2006 2 2 2 67 2 2
"1010A2332" 2009 2 2 2 69 2 2
"1010A2332" 2003 3 3 1 33 1 5
"1010A2332" 2006 3 3 1 35 1 4
"1010A2332" 2009 3 3 1 39 1 5
"1010A2332" 2003 4 3 2 22 1 5
"1010A2332" 2006 4 3 2 25 1 5
"1010A2332" 2009 4 3 2 28 1 5
"1010A2332" 2003 5 3 2 39 1 4
"1010A2332" 2006 5 3 2 41 1 4
"1010A2332" 2009 5 3 2 45 1 4
"1010A2332" 2006 6 6 2 15 1 3
"1010A2332" 2006 7 6 1  5 1 0
"1010A2440" 2003 1 1 1 50 2 2
"1010A2440" 2006 1 1 1 54 2 2
"1010A2440" 2009 1 1 2 55 3 4
"1010A2440" 2003 2 2 2 49 2 2
"1010A2440" 2006 2 2 2 52 2 2
"1010A2440" 2009 2 3 1 23 1 5
"1010A2440" 2003 3 3 1 24 1 3
"1010A2440" 2006 3 3 1 26 1 2
"1010A2440" 2009 3 3 1 30 2 4
"1010A2440" 2003 4 3 1 23 1 3
"1010A2440" 2006 4 3 2 23 1 1
"1010A2440" 2003 5 3 2 20 1 2
"1010A2440" 2006 5 3 1 22 1 4
"1010A2440" 2003 6 3 1 19 1 3
"1010A2440" 2003 7 3 2 17 1 3
"1010A2440" 2009 8 3 2 22 2 4
"1010A2440" 2009 4 5 2 25 2 4
"1010A2440" 2009 7 5 1 22 2 4
end
label values rel REL
label def REL 1 "Head", modify
label def REL 2 "Wife/Spouse", modify
label def REL 3 "Son/daughter", modify
label def REL 5 "Son/daughter_law", modify
label def REL 6 "Grandchildren", modify
label values sex SEX
label def SEX 1 "Male", modify
label def SEX 2 "Female", modify
label values marstat MSTAT
label def MSTAT 1 "Single", modify
label def MSTAT 2 "Married", modify
label def MSTAT 3 "Widowed", modify
label values educ GRADE
label def GRADE 0 "No Grade Completed", modify
label def GRADE 1 "Elementary Undegraduate", modify
label def GRADE 2 "Elementary Graduate", modify
label def GRADE 3 "Highschool Undergraduate", modify
label def GRADE 4 "Highschool Graduate", modify
label def GRADE 5 "Collge Undergraduate", modify

[Carlo Lazzaro]

Zarah:
welcome to this forum.
You may want to try:

.egen wanted=group( zzhhid)

I fear what above won't help as expected: by the way, what does -lno- mean?

[Zarah Jimenez]

Thank you very much for the suggestion. I will try if it works out.
My apologies, I guess I wasn't very clear with my explanation. "lno" is the variable indicating the line number of the individual respondent in the survey. I was initially planning on using it to create ID at person level but it was so useful since the line number of the respondents vary year to year.

[Carlo Lazzaro]

Zarah:
what if you type:

.egen wanted=group( zzhhid rel)

[Zarah Jimenez]

Sorry it took a while to get back to the forum. I had barely managed to do so with the suggested command but using household id, age and sex. For some confidence, I also did some sort of reasonableness check based on educational attainment of individuals. I allowed individuals to have an increase, but not a decrease in educational attainment from survey round to the next survey round. Plenty observations were dropped but I ended with enough.

Thank you again.