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Re: st: If variable x contains variable y

 From To Subject Re: st: If variable x contains variable y Date Sun, 15 Jul 2012 16:52:26 +0100

```Hi,

Thanks for your help. It's a bit more tricky than that, at least as far
as I can tell. I'll try and explain a little more clearly! So, as below,
I have household level and individual level identifiers. I essentially
want to flag the mother's idno. So something along the lines of gen x=1
if idno=="any value in mother_id" to look like column x below. Whether
column x read 1 or the corresponding idno is not important at this
stage. And I agree, these probably should be stored as string, it's not
my data!

idhouseidnomother_idx
1736641
173665
173666
17366773664
173668
294038
2940391
294040
2940411
294042
2940431
29404494041
29404594039
2940461
29404794046
29404894046
294049
294050
29405194043
294052

Thanks for your help!
John

>>> Christoph Engel  15/07/12 4:21 PM >>>
John,

You will have to define the value of x if y does not fulfil your
condition, i.e. if it is not equal to z. Depending on your purposes you
might either want it to be a missing value, or some expression of x, say

0. I would therefore start out

gen x = .
replace x = y if y == z

(note the "==" in the if clause)

Best

Christoph Engel

Am 7/15/2012 4:59 PM, schrieb Steve Nakoneshny:
> John,
>
> At first glance, it would seem that -gen x = y if y = z- would serve
as a solution. Of course, this assumes that your I'd vars are numerical
and not string vars (which they probably should be stored as).
>
> Steve
>
> Sent via carrier pigeon
>
> On 2012-07-15, at 8:52 AM, "john.guzek@lshtm.ac.uk"  wrote:
>
>> Hello,
>>
>>
>> This is my first time using statalist, I hope I do this all
correctly!
>>
>>
>> I'm looking to create a variable x which is equal to y, but only if
the given value for y can be found in another variable, z. These are all
id numbers, so say y is a universal id and z is a mother's id, telling
you the universal id of the mother in relation to the child.
>>
>>
>> For example:
>>
>>
>> yzx
>>
>>
>> 1..
>> 2.2
>> 3.3
>> 42.
>> 5..
>> 6..
>> 737
>> 8..
>> 9..
>> 107.
>>
>>
>> So I'm trying to figure out how to create x. Any help would be much
appreciated.
>>
>>
>> Thanks,
>> John
>>
>>
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--
_________________________________________________________________
Prof. Dr. Christoph Engel
Max-Planck-Institut zur
Erforschung von Gemeinschaftsgütern
Max Planck Institute for Research on Collective Goods
Kurt-Schumacher-Strasse 10
D 53113 Bonn
Tel. +49/228/91416-10
Fax +49/228/91416-11
e-mail:engel@coll.mpg.de
http://www.coll.mpg.de
http://www.coll.mpg.de/engel.html
http://ideas.repec.org/e/pen22.html
http://papers.ssrn.com/sol3/cf_dev/AbsByAuth.cfm?per_id=251559
_________________________________________________________________

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```