Statalist


[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

Re: st: SAS to Stata


From   "Raphael Fraser" <raphael.fraser@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: SAS to Stata
Date   Fri, 22 Aug 2008 09:42:13 -0500

I think I found the solution but while the covariance for the random
effects parameters are the same the variances are not. I can't imagine
that they are using different methods! BUT some thing is off here. The
coefficients and standard error for the fixed effects are exactly the
same. Is there a reasonable explanation?
 Thank you.

SAS

PROC MIXED NOCLPRINT=10 ORDER=data;
       CLASS id group time;
       MODEL y = group time group*time / SOLUTION CHISQ;
       REPEATED time / TYPE = un SUBJECT = id R;
RUN;

STATA

xtmixed y group time1 time4 time6 groupXtime1 groupXtime4 groupXtime6 || ///
	id: time0 time1 time4 time6, nocons cov(unstructured) variance

Raphael


On Wed, Aug 20, 2008 at 3:48 PM, Stas Kolenikov <skolenik@gmail.com> wrote:
> That's some sort of the hierarchical linear model...
>
> xi: xtmixed y i.group i.time i.group*time || id: , cov(unstructured)
>
> is all I can think of.
>
> On Wed, Aug 20, 2008 at 2:44 PM, Raphael Fraser
> <raphael.fraser@gmail.com> wrote:
>> Can anyone convert this SAS code to Stata?
>>
>> PROC MIXED NOCLPRINT=10 ORDER=data;
>>        CLASS id group time;
>>        MODEL y = group time group*time / SOLUTION CHISQ;
>>        REPEATED time / TYPE = un SUBJECT = id R;
>> run;
>>
>> Raphael
>> *
>> *   For searches and help try:
>> *   http://www.stata.com/help.cgi?search
>> *   http://www.stata.com/support/statalist/faq
>> *   http://www.ats.ucla.edu/stat/stata/
>>
>
>
>
> --
> Stas Kolenikov, also found at http://stas.kolenikov.name
> Small print: I use this email account for mailing lists only.
> *
> *   For searches and help try:
> *   http://www.stata.com/help.cgi?search
> *   http://www.stata.com/support/statalist/faq
> *   http://www.ats.ucla.edu/stat/stata/
>
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index