xtfrontier trade pgdpi pgdpj popi popj dis,ti nolog
convergence not achieved
Time-invariant inefficiency model Number of obs = 135
Group variable: id Number of groups = 9
Obs per group:
min = 15
avg = 15
max = 15
Wald chi2(5) = 390.25
Log likelihood = -939.9249 Prob > chi2 = 0.0000
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trade | Coef. Std. Err. z P>|z| [95% Conf. Interval]
-------------+----------------------------------------------------------------
pgdpi | .6835968 .0996536 6.86 0.000 .4882794 .8789142
pgdpj | -.3962061 .0510653 -7.76 0.000 -.4962922 -.29612
popi | -.0000202 7.21e-06 -2.80 0.005 -.0000343 -6.04e-06
popj | -7.36e-07 4.16e-06 -0.18 0.860 -8.89e-06 7.42e-06
dis | 3.8789 1.469537 2.64 0.008 .9986603 6.75914
_cons | 17470.66 4548.906 3.84 0.000 8554.972 26386.36
-------------+----------------------------------------------------------------
/mu | .0001883 . . . . .
/lnsigma2 | 16.28461 .4821928 33.77 0.000 15.33953 17.22969
/lgtgamma | 5.662036 .5007541 11.31 0.000 4.680576 6.643496
-------------+----------------------------------------------------------------
sigma2 | 1.18e+07 5695554 4590627 3.04e+07
gamma | .9965366 .0017283 .9908115 .9986992
sigma_u2 | 1.18e+07 5695583 607731.2 2.29e+07
sigma_v2 | 40908.86 5155.826 30803.63 51014.09