Re: st: xtfrontier

[mohamm52@msu.edu]

Dear Federico,

I used both alternatives and got the same results. Does it mean there  
is no need to be worry?

Thank you

Rezgar,


Quoting Federico Belotti <f.belotti@gmail.com>:

> It seems like your compounded error term is normal. In this case  
> there is no evidence of inefficiency (i.e all firms are technically  
> efficient). Alternatives are: 1) change model specification; 2) try  
> a different SF model (see -ssc describe sfpanel-).
>
> HTH,
> Federico
> On Jul 13, 2013, at 6:35 PM, mohamm52@msu.edu wrote:
>
> > Dear Statalist,
> >
> > I recently used xtfrontier for my paper and I got some problems. I  
> > would like to estimate the technical efficiency of rice farms in  
> > some provinces between 1993-2012 using panel data. I have output as  
> > a dependent variable and each labor, fertilizer, land, seed and  
> > capital as independent variables. What makes me worry is that, for  
> > each province I have the same value of the technical efficiency for  
> > all the years and all the values are between 0.99-1.0 which is hard  
> > to believe.
> > I used the following commands
> > xtset   province   year
> > panel   variable:   province (strongly balanced)
> > time   variable:   year, 1993 to 2012
> > delta:    1 unit
> > xtfrontier  lny  lnx1  lnx2  lnx3  lnx4  lnx5,  tvd
> > predict efficiency, te
> >
> > Any suggestion please.
> >
> > *
> > *   For searches and help try:
> > *   http://www.stata.com/help.cgi?search
> > *   http://www.stata.com/support/faqs/resources/statalist-faq/
> > *   http://www.ats.ucla.edu/stat/stata/
>
> --
> Federico Belotti, PhD
> Research Fellow
> Centre for Economics and International Studies
> University of Rome Tor Vergata
> tel/fax: +39 06 7259 5627
> e-mail: federico.belotti@uniroma2.it
> web: http://www.econometrics.it
>
>
> *
> *   For searches and help try:
> *   http://www.stata.com/help.cgi?search
> *   http://www.stata.com/support/faqs/resources/statalist-faq/
> *   http://www.ats.ucla.edu/stat/stata/



*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/faqs/resources/statalist-faq/
*   http://www.ats.ucla.edu/stat/stata/