Re: st: RE: Changing beta coefficients - w/ logistic regression

[Richard Williams <Richard.A.Williams.5@ND.edu>]

At 05:33 PM 7/21/2005 -0500, Scott Merryman wrote:
> Change the program to:
>
> program foo2, eclass
>          tempname bmat
>          matrix `bmat' = e(b)
>          matrix b = e(b)
>          ereturn post b
>          matrix `bmat'[1,1] = 122
>          ereturn repost b = `bmat'
> end
>
> This seems to work for both -regress- and -logit-
>
> Scott
I'm surprised the original program doesn't work.  Something to be aware of 
with Scott's solution:  most of the ereturned stuff gets zapped once you 
run foo2.  In particular, since e(predict) gets zapped, the p option on 
predict doesn't work.  You can probably add lines to Scott's program to 
revive the ereturned stuff that gets lost but maybe there is a better 
way.  The following shows what I am talking about:


. sysuse auto
(1978 Automobile Data)
. qui logit  foreign mpg weight
. ereturn list

scalars:
...Bunch of stuff...

macros:
             e(title) : "Logistic regression"
            e(depvar) : "foreign"
               e(cmd) : "logit"
          e(crittype) : "log likelihood"
           e(predict) : "logit_p"
        e(properties) : "b V"
         e(estat_cmd) : "logit_estat"
          e(chi2type) : "LR"

matrices:
                 e(b) :  1 x 3
                 e(V) :  3 x 3

functions:
            e(sample)

. predict prob1, p
. foo2
. ereturn list

macros:
        e(properties) : "b"

matrices:
                 e(b) :  1 x 3

. predict prob2, p
option p not allowed
r(198);



-------------------------------------------
Richard Williams, Notre Dame Dept of Sociology
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