05-07-2012 12:28 PM
I am running a half-normal production frontier analysis with proc QLIM.
I would like to be able to get the technical efficiencies to match up to STATA using
frontier. I have been unable to get the same results from both packages.
qlim data=work_dataset1 METHOD=NEWRAP covest=hessian;
model lnAAA = lnBBB lnCCC lnDDD;
endogenous lnAAA ~ frontier (type=HALF production);
output out = work_out1 TE1 TE2 EXPECTED;
The documentation for the technical efficicneies in SAS are
produces estimates of the technical efficiency via TE = E(exp(-u|e)]
This has been documented as derrived from (by Battese and Coelli (1988) too?
and can also produce
produces estimates of minus the natural log of the technical efficiency via TE = exp(-E(u|e)]
produces estimates of minus the natural log of the technical efficiency via TE = exp(-M(u|e)]
Has anyone been able to get the same resutls from QLIM and frontier? Any suggestions?