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# Re: st: generate a new categorical variable

 From Alan Neustadtl To statalist@hsphsun2.harvard.edu Subject Re: st: generate a new categorical variable Date Thu, 13 Sep 2012 22:37:09 -0400

```How about -egen group- something like this:

clear
input Y str1 Z
1 A
1 B
0 C
1 D
1 Y
1 A
1 B
0 C
1 D
1 Y
end

egen comb=group(Y Z)
tab1 Y Z comb

Best,
Alan

On Thu, Sep 13, 2012 at 3:53 PM, urbain thierry YOGO <yogout@gmail.com> wrote:
> Dear all
> i have two variables Y and Z. Y is a dummy variable which takes 1 if
> individual has access to water and 0 otherwise. Z is a categorical
> variable which has the following structure:
> Z=A if individual uses bleach to clean water
> Z=B if individual use a filter to clean water
> Z=C if individual use solar energy to clean water
> Z=D if individual use absorbent cotton to clean water
>
> Here is my problem. I want to generate a new variable X which should
> be a combination of Y and Z. Here is the code i have written
> gen X=0 if Y==0
> replace X=1 if Y==1 & Z=="A"
> replace X=2 if Y==1 & Z=="B"
> replace X=3 if Y==1 & Z=="C"
> replace X=4 if Y==1 & Z=="D"
>
> My concern is that when i write this code, the first two lines work,
> but after, there is 0 replacement. Please can somebody help me? Thank
>
> --
> *Urbain Thierry YOGO
> Ph.D candidate in Economics*
> *
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```