--- Walter Forrest <[email protected]> wrote:
> predictnl seems to be the right option, but when I've run it I've
> received an error message that reads "too many variables specified".
> Any ideas as to what I'm doing incorrectly?
>
> Here's my code:
>
> tobit depvar `x1' `x2' `x3', ll
> predict xb if e(sample)
>
>
> */
> local big=normal(xb/_b[/sigma])
> local small=normalden(xb/_b[/sigma])
>
>
> */ the following gets an error message
>
predictnl=((_b[`x3']*`big')+(1/_b[/sigma])*((_b[`x1']*_b[`x2'])+(_b[`x1']*_b[`x3']*`x1')
> + (_b[`x2']*_b[`x3']*`x2') + (_b[`x3']*_b[`x3']*`x1'*`x2')) *
> `small'), se(inteff_se)
I see two things:
1) xb should be xb()
2) you need to specify the variable in which you store these effects,
something like:
predictnl eff = ((_b[`x3']* ...
Hope this helps,
Maarten
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room N515
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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