Bookmark and Share

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.


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: Calculating predicted probabilities at a given value of one of the independent variables


From   Richard Williams <richardwilliams.ndu@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: Calculating predicted probabilities at a given value of one of the independent variables
Date   Thu, 27 Oct 2011 00:59:55 -0500

At 10:05 PM 10/26/2011, Vitorino, Maria Ana wrote:
Thanks!! But the results should be the same as in your previous suggestion, right? Or am I missing something?

Also, -help predict- talks about in-sample and out-of-sample predictions. An interesting example it gives shows how you could run the estimation on one sample and then compute the predictions using a totally different sample.

Ana


On Oct 26, 2011, at 10:53 PM, "Richard Williams" <richardwilliams.ndu@gmail.com> wrote:

> At 06:06 PM 10/26/2011, Maria Ana Vitorino wrote:
>> Dear Statalist users,
>>
>> I would like to calculate some predicted probabilities after fitting a
>> multinomial logit model (asclogit). But, the twist is that I would
>> like to calculate these fitted values for a given level of one of the
>> independent variables. Namely, I would like to set one of the Xs to
>> zero when computing the predicted probability (but not in the
>> estimation).
>> What would be the best way of going about this? Would it make sense to
>> do it in 2 steps? In the first step use  "predict xb" and in the
>> second step remove the component of xb that I'm not interested and
>> calculate the probability using "gen" and the logit formula?
>> Or is there a better way?
>
> I am going to slightly tweak my earlier advice. Assuming you only want in-sample predictions,
>
> webuse sysdsn1, clear
> clonevar xmale = male
> mlogit insure age i.xmale nonwhite i.site
> predict p1 p2 p3 if e(sample)
> replace xmale = 0 if !missing(xmale)
> predict pp1 pp2 pp3 if e(sample)
>
>
> -------------------------------------------
> Richard Williams, Notre Dame Dept of Sociology
> OFFICE: (574)631-6668, (574)631-6463
> HOME:   (574)289-5227
> EMAIL:  Richard.A.Williams.5@ND.Edu
> WWW:    http://www.nd.edu/~rwilliam
>
> *
> *   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/

-------------------------------------------
Richard Williams, Notre Dame Dept of Sociology
OFFICE: (574)631-6668, (574)631-6463
HOME:   (574)289-5227
EMAIL:  Richard.A.Williams.5@ND.Edu
WWW:    http://www.nd.edu/~rwilliam

*
*   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   |   Site index