Stata The Stata listserver
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

RE: st: Predictions based on reoprob and gllamm


From   "Erik Melander" <erik.melander@pcr.uu.se>
To   <statalist@hsphsun2.harvard.edu>
Subject   RE: st: Predictions based on reoprob and gllamm
Date   Sat, 28 Feb 2004 12:19:52 +0200

Thanks for the explanation!

Now my problem is that whatever I try with gllapred I get "insufficient
observations" in return. I have 2237 observations of 153 countries from the
years 1976-1995 (unbalanced dataset).

Given that I have too few observations for gllapred, how can I then present
my results so that the substantial impact of the most interesting
independent variables can be appreciated?

Thanks for your attention.

Erik

> -----Original Message-----
> From: owner-statalist@hsphsun2.harvard.edu
> [mailto:owner-statalist@hsphsun2.harvard.edu]On Behalf Of Sophia
> Rabe-Hesketh
> Sent: Friday, February 27, 2004 9:44 PM
> To: statalist@hsphsun2.harvard.edu
> Subject: Re: st: Predictions based on reoprob and gllamm
>
>
> The thresholds are applied to the latent response y*
> underlying the observed response y.
> y* can take on any value from - infinity to + infinity.
> If the lowest observed response category, say 1, happens
> very rarely, the lowest threshold may have to be a large
> negative number because Pr(y=1) = Pr(y*<threshold)
> and similarly for the largest category.
>
> I am not sure what predictions you have considered.
> If you are referring to 'xb' (the linear predictor),
> then this is the mean of the latent response y* which
> doesn't need to lie on the range of y.
>
> In gllamm, you can obtain the predicted (population
> averaged) cumulative probabilities, e.g., Pr(Y>1) using
>
> gllapred probgr1, mu above(1) marg
>
> and similarly for the other categories.
>
> You can also get predicted probabilities for particular
> values of the random effects or posterior mean probabilities.
>
> Sophia

*
*   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/



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