Re: st: AW: combining datasets

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Wed, 18/8/10, martine etienne wrote:
> ...well the unique identifiers are id
> variables, i guess i want to know which is 
> a better method, I don't want to lose the unique ids

That still really depends on what you want to do and 
what is in those datasets.

Say we have two dataset:
A:

id x
1  3
2  4

B:

id x
1  5
2  6

The first question is: is person 1 in dataset A the same person
as person 1 in dataset B, e.g. are they measurements taken
at different times. 

The second question is: what do you want your final dataset to 
look like, Final 1 or Final 2? (Final 2 is only possible if you
answered yes to question 1)

Final 1
id source x
1  A      3
2  A      4
1  B      5
2  B      6

Final 2
id xA xB
1  3  5
2  4  6

Hope this helps in pinning down your question,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------



      

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