# Re: st: predict or adjust after logistic?

 From Joanne Garrett <[email protected]> To [email protected] Subject Re: st: predict or adjust after logistic? Date Thu, 24 Apr 2003 13:55:09 -0400

```I've just updated predxcat.ado (predictions for categorical X variables)
and predxcon.ado (predictions for continuous X variables) for version
8.0 of Stata to take advantage of the new graphics. These programs
calculated adjusted means or probabilities for linear or logistic
regression. The same results can be accomplished with the "adjust"
command in Stata. However, these programs more easily graph the results,
calculate confidence intervals, add polynomial terms, test for
interaction, etc.  (these are also rewrites of much older programs --
list. If anyone is interested in using them, I'd love some feedback.
Joanne G.

[email protected] wrote:
>
> Greg wrote:
>
> To predict  probabilities and 95% CIs of the predicted probabilities after
> a multivariate  logistic model, I have previously used the following
> predict  command:
>
> logistic y x1 x2  x3
> predict lr_index,  index
> predict se_index,  stdp
>
> gen p_hat =  exp(lr_index)/(1 +exp(lr_index))
> gen lb = lr_index -  invnorm(0.975)*se_index
> gen ub = lr_index +  invnorm(0.975)*se_index
> gen plb =  exp(lb)/(1+exp(lb))
> gen pub =  exp(ub)/(1+exp(ub))
>
> bysort x1: tabstat  p_hat plb pub
>
> Check out:
>
> Predxcon or predxcat
>
> or
>
> logpred , regpred
>
> or
>
> The commands at Scott Long's Homepage (http://www.indiana.edu/~jslsoc/)
>
> Christer
>
>
>                       "Daniel, Gregory"
>                       <[email protected]>         To:       "'[email protected]'" <[email protected]>
>                       Sent by:                         cc:
>                       owner-statalist@hsphsun2.        Subject:  st: predict or adjust after logistic?
>                       harvard.edu
>
>
>                       02.04.03 21:54