Thank you Allin
Best regards
Simona
2015-04-29 19:11 GMT+02:00 Allin Cottrell <cottrell(a)wfu.edu>:
On Wed, 29 Apr 2015, Simona De Lauretis wrote:
Dear Gretl users,
>
> I have a question about system estimation and a (possible) bug report.
>
> The question is: is it possible to include weights for observations when
> estimating a system of equations in gretl (with sur method for example)?
>
> I've read in the command reference that the supported estimators
> are ols, tsls, sur, 3sls, fiml and liml. However, if I estimate the
> system using the
> "simultaneous equations" dialog box, there is also wls as one of the
> proposed estimators
>
> (but it's not possible to specify a weight variable, so maybe it does
> not perform a
> weighted regression after all).
>
Thanks for the report. The "wls" option has somehow slipped through
undocumented, we need to fix that. But it's not intended that the user can
supply weights, rather the idea is that weights are derived from
the relative variances of the error terms in the equations of the system.
It's the same use of "wls" as in the systemfit package for R, in case
you've come across that. See
http://cran.r-project.org/web/packages/systemfit/systemfit.pdf
for brief documentation.
The possible bug occurs after the estimation of a system using method
> SUR. In the results window, the command "Tests -> Normality of
residuals"
> is active, but nothing happens when I click on it (gretl does not crash
> either).
>
I see what you mean. For some reason the normality test via the GUI was
not hooked up to its "callback" to actually do the job (or actually, was
hooked up only for models estimated on time-series data). That's now fixed
in CVS and gretl snapshots.
Allin Cottrell
_______________________________________________
Gretl-users mailing list
Gretl-users(a)lists.wfu.edu
http://lists.wfu.edu/mailman/listinfo/gretl-users