Re: st: st : Problem of no enough observations

["Brian P. Poi" <bpoi@stata.com>]

On Fri, 16 Nov 2007 Valerie (orozco@toulouse.inra.fr) wrote:

> I wonder why Stata tells me that I haven't enough observations to estimate my
> system of equations with "NLSUR". ("cannot have fewer observations than
> parameters")
>
> In fact, I have a system of equations to estimate. One equation per good `i' :
> (the coefficients I have to estimate are between the braces {}.)
>
> dw`i' = {b`i'} *ddeflexp + {g`i'vs1} * dlnp1+ {g`i'vs2} *  dlnp2+ {g`i'vs3} *
> dlnp3 + {g`i'vs4} * dlnp4 + {g`i'vs5} *  dlnp5 + {g`i'vs6} * dlnp6 + {g`i'vs7}
> * dlnp7 + {g`i'vs8} * dlnp8 + {g`i'vs9} * dlnp9 + {g`i'vs10} * dlnp10 +
> {g`i'vs11} * dlnp11 + {g`i'vs12} * dlnp12 )
>
> As you can see, I have 13 coefficients to estimate for each good `i'
> (i=1,...,12)
> I have 78 observations. The problem just comes because I think Stata calculate
> the total number of coefficients(13 * 12 = 156), but in fact I have only 13 per
> good...
If Valerie would send directly to me (bpoi@stata.com) her dataset and a 
short do-file, I'd be happy to look into this issue for her.

   -- Brian Poi
   -- bpoi@stata.com
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