Brent--
Ignoring more "statistical" solutions such as multiple imputation or
estimating conservative SEs by ignoring strata, suppose you quietly
regress without -svy- then calculate n of PSUs per stratum if
e(sample) then issue a -levelsof- strata if the n exceeds 1, e.g.
qui reg y $x if !mi(weight,psu,strata)
g u_psu=1 if e(sample)
egen n_psu=count(u_psu), by(strata)
levelsof strata if n_psu>1, local(ok)
local oklist: subinstr loc ok " " ",", all
drop n_psu u_psu
svy, subpop(inlist(strata,`oklist')): reg y $x
Does that work?
On 12/16/06, Brent Fulton <[email protected]> wrote:
I am using Stata 9.2 and am running -svy: reg y x1 x2- using a svyset with
pweights, strata id, and psu id. Stata will not estimate standard errors if
a stratum has a single psu.
And Stata estimates the standard errors.
Is there a way to make this process dynamic. For example, when I change the
regression to:
svy: reg y x1 x2 x3
then missing values in x3 may cause another stratum to have one psu. I'd
like to be able to run -svydes y x1 x2 x3-, put the results into a matrix,
and search for strata with one psu, and identify the strata using a macro.
svy: subpop(!inlist(strata_id, $macro_of_strata_with_one_psu)): reg y x1 x2
x3
However, -return list- and -ereturn list- are empty after running -svydes y
x1 x2 x3-. Does anyone have any suggestions?
Lastly, is there another way to estimate the standard errors using Stata (or
using another statistical program e.g., SUDAAN; or bootstrap) when a
stratrum has a single psu.
Thanks,
Brent
___________________________________
Brent D. Fulton, PhD
Health Services Researcher
Petris Center at UC Berkeley
Phone: 510-643-4102
Fax: 510-643-4281
Email: [email protected]
www.petris.org
*
* 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/
*
* 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/
