Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down on April 23, and its replacement, statalist.org is already up and running.

# Re: st: proportion confidence intervals <0 and >1 in MI SVY

 From Steve Samuels To statalist@hsphsun2.harvard.edu Subject Re: st: proportion confidence intervals <0 and >1 in MI SVY Date Tue, 11 May 2010 11:18:36 -0400

```There's an error someplace in this program, so please disregard for
the time being.

Steve

On Tue, May 11, 2010 at 10:46 AM, Steve Samuels <sjsamuels@gmail.com> wrote:
> I don't have an -mi- example, but here is an example with plain -svy: prop-
> -Steve
>
> ************CODE BEGINS***********
> capture program drop _all
> program backlogit
> nlcom log(\$parm/(1-\$parm))
> scalar lparm = el(r(b),1,1)
> scalar se  =  sqrt(el(r(V),1,1))
> scalar bound = invttail(e(df_r),.025)*se
> scalar ll = exp(lparm -bound*se)
> scalar ul = exp(lparm +bound*se)
> scalar ll = ll/(1+ll)
> scalar ul = ul/(1+ul)
> di %9.4f \$parm   %9.4f ll  %9.4f ul
> end
>
> sysuse auto,clear
> svyset _n
> svy: prop rep78
> global parm _b[1]
> backlogit
> ********CODE ENDS*********************
>
> On Tue, May 11, 2010 at 8:44 AM, Paul Shattuck <pshattuck@wustl.edu> wrote:
>> Hi,
>>
>> I am analyzing imputed survey data using the MI SVY estimation commands. I am estimating proportions and requesting confidence intervals (syntax below). However, many of the confidence intervals are falling outside of 0,1 bounds. The tab confidence intervals available in plain SVY (without MI) are generated using a logistic transform that prevents this problem. However, the tab procedure is not available in MI estimation.
>>
>> Can anyone suggest a work-around that will let me obtain proportion confidence intervals in MI SVY estimation that remain within the 0,1 bounds?
>>
>> mi estimate: svy, subpop(if var1==1): proportion var2
>>
>> Thank you,
>>
>> Paul
>>
>>
>>
>>
>>
>> *
>> *   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/
>>
>
>
>
> --
> Steven Samuels
> sjsamuels@gmail.com
> 18 Cantine's Island
> Saugerties NY 12477
> USA
> Voice: 845-246-0774
> Fax:    206-202-4783
>

--
Steven Samuels
sjsamuels@gmail.com
18 Cantine's Island
Saugerties NY 12477
USA
Voice: 845-246-0774
Fax:    206-202-4783

*
*   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/
```