# Re: st: testing 2 proportions using svytab

 From Nick Winter To statalist@hsphsun2.harvard.edu Subject Re: st: testing 2 proportions using svytab Date Fri, 18 Feb 2005 11:51:57 -0500

I thin kit would be equivalent to do:

. svymean dummy if cat4==1
. test dummy=0.5

And similarly for the other values of cat4. That is, if the two proportions are equal, then the mean of the dummy variable will be 0.5.

--Nick

At 10:02 AM 2/18/2005 -0500, you wrote:

```Hello all,

Hopefully I have solved this, but wanted to see if this made sense:

> I am using svytab to look at different proportions of a 4 value
> category by an indicator variable:
>
> svytab dummy cat4,  row se
> ------------------------------
>    1   2   3   4
> 0   a   b   c   d
> 1   e   f   g   h
> ------------------------------
>
> test a==e, etc...
>
> I would like to test whether or not the row proportions for each
> category of cat4 are significant from the opposite by indicator. I
> assume I can do this using the standard error, but am unsure of how to
> code this.

after I :

svytab dummy cat4,  row format(%12.3f) se

I can then

test _b[p11]=_b[p21]
test _b[p12]=_b[p22]
.....etc

Is this test valid (variance-wise) for a test that two proportions
from the same survey are different, given the use of svytab?

Other relevant posts include:

http://www.stata.com/statalist/archive/2004-05/msg00975.html
http://www.stata.com/statalist/archive/2002-10/msg00420.html

Any help is appreciated,

Dan
*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/
```
--------------------------------------------------------
Nicholas Winter 607.255.8819 t
Assistant Professor 607.255.4530 f
Department of Government nw53@cornell.edu e
308 White Hall falcon.arts.cornell.edu/nw53 w
Cornell University
Ithaca, NY 14853-4601

*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/