# Computing new variable from variable with multiple observations fromthe same respondent

Discussion in 'SPSS' started by Jeppe Christensen, Oct 12, 2011.

1. ### Jeppe ChristensenGuest

Confusing subject, but it's hard to describe.

I have two variables:

var1. Variable with a unique respondent number
var2. Variable with a study number (1-3)

The respondents can have participated in one, two or three studies,
and they will figure a corresponding number of times on my two
variables. So a unique respondent can figure multiple times in the
data, with different values on var2.

Problem: I want to compute a new variable that tells me which studies
the respondents have participated in.

Regards
Jeppe

Jeppe Christensen, Oct 12, 2011

2. ### Bruce WeaverGuest

Do you mean you want a single new variable added to the data file with
multiple rows (potentially) per ID? Something like this will do it, I
think.

* Read in some data to illustrate.
new file.
dataset close all.
data list list / ID StudyNum (2f5.0).
begin data
1 1
1 2
2 3
3 2
3 3
4 1
4 2
4 3
5 1
6 2
end data.

AGGREGATE
/BREAK=ID
/f1=FIN(StudyNum 1 1)
/f2=FIN(StudyNum 2 2)
/f3=FIN(StudyNum 3 3)
..

compute Studies = (f1 GT 0) + (f2 GT 0)*10 + (f3 GT 0)*100.
variable labels Studies "Studies for this ID".
value labels Studies
1 "S1"
10 "S2"
11 "S1, S2"
100 "S3"
101 "S1, S3"
110 "S2, S3"
111 "S1, S2, S3"
..
frequencies Studies.
delete variables f1 to f3.

If this is not what you're after, please clarify.

Bruce Weaver, Oct 12, 2011

3. ### Jeppe ChristensenGuest

Thanks a lot Bruce, your syntax proved to be the solution

/Jeppe

Jeppe Christensen, Oct 14, 2011