Re: st: sem - is it possible to drop error terms?

[John Antonakis <John.Antonakis@unil.ch>]

If you show your syntax maybe someone could help you.
Best,
J.

__________________________________________

John Antonakis
Professor of Organizational Behavior
Director, Ph.D. Program in Management

Faculty of Business and Economics
University of Lausanne
Internef #618
CH-1015 Lausanne-Dorigny
Switzerland
Tel ++41 (0)21 692-3438
Fax ++41 (0)21 692-3305
http://www.hec.unil.ch/people/jantonakis

Associate Editor
The Leadership Quarterly
__________________________________________

On 12.03.2013 20:17, Jacob Felson wrote:
> Stas,
>
> Thanks!  Its strange -- when I try to run a basic behavior genetic
> model (ACE) using Stata's sem command, I immediately receive an error
> saying there are too many latent variables and the model is not
> identified.  But this model is definitely identified -- at least
> theoretically.  Model is here:
> http://www.biomedcentral.com/1471-2202/5/49/figure/F1?highres=y
>
> Sorry to bother you.  Any help you could provide is much appreciated.
>
> Sincerely,
>
> Jacob Felson
>
>
>
> On Tue, Mar 12, 2013 at 2:59 PM, Stas Kolenikov <skolenik@gmail.com> wrote:
> > Jacob,
> >
> > you can constrain the variance of these error terms to zero with
> > -variance()- option of -sem-.
> >
> > -- Stas Kolenikov, PhD, PStat (SSC)
> > -- Senior Survey Statistician, Abt SRBI
> > -- Opinions stated in this email are mine only, and do not reflect the
> > position of my employer
> > -- http://stas.kolenikov.name
> >
> >
> >
> > On Tue, Mar 12, 2013 at 1:53 PM, John Antonakis <John.Antonakis@unil.ch> wrote:
> > > Hi Jacob:
> > >
> > > You need to be much more specific about what specific model you wish to test
> > > (write-out equations or syntax). Most probably don't know what ACE is:
> > >
> > > http://www.stata.com/support/faqs/resources/statalist-faq/
> > >
> > > Best,
> > > J.
> > >
> > > __________________________________________
> > >
> > > John Antonakis
> > > Professor of Organizational Behavior
> > > Director, Ph.D. Program in Management
> > >
> > > Faculty of Business and Economics
> > > University of Lausanne
> > > Internef #618
> > > CH-1015 Lausanne-Dorigny
> > > Switzerland
> > > Tel ++41 (0)21 692-3438
> > > Fax ++41 (0)21 692-3305
> > > http://www.hec.unil.ch/people/jantonakis
> > >
> > > Associate Editor
> > > The Leadership Quarterly
> > > __________________________________________
> > >
> > >
> > > On 12.03.2013 19:30, Jacob Felson wrote:
> > > > I'm wondering if its possible to drop the error terms that are
> > > > included by default in sem models.  I've searched in the manual and
> > > > online but I can't find any indication that this is possible.  I
> > > > imagine its not, but I wanted to check with the experts to make sure.
> > > >
> > > > (I'm estimating a behavior genetic model with data on MZ and DZ twins
> > > > -- the so-called ACE model.)
> > > >
> > > >
> > > > Thank you,
> > > >
> > > >
> > > > Jacob Felson
> > > > *
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> > >
> > > *
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>
>
> --
> Jacob Felson
> *
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*
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