My first reaction was: just continue using Frontier 4.1!!! It's far better than Stata!!!
For the serious reply, I quote from myself (please NOTE that things may have changed in Stata 10!): "Frontier 4.1 let you express the technical inefficiency term as a linear combination of some variables. INEXPLICABLY, Stata (just-updated, Intercooled, version 9.2) let you do this only for the cross-sectional command -frontier-, but not for the panel counterpart -xtfrontier-. In the latter command, the inefficiency term can be only a random variable with truncated-normal distribution, or a random variable with truncated-normal distribution multiplied by a specific function of time (exponential decay)"
P.S. I'll NOT receive/read any email but the Digest.
At 02.33 20/11/2008 -0500, you wrote:
>Dear Statalist Members,
>I have an unbalanced panel data set at hand and want to estimate
>agricultural production functions. In Frontier 4.1 there is the
>possibility to specify the explanatory variabels and variables
>explaining unit specific reasons for inefficiency separately. Does
>some porcedure exist in Stata to obatain the parameters of an
>inefficiency model with Stata?
>Every comment is appreciated.