关于Frontier的一些疑问

the final mle estimates are :                  coefficient     standard-error    t-ratio   beta 0        -0.16374349E+00  0.34711337E+00 -0.47172915E+00   beta 1         0.72471519E+00  0.73871935E-01  0.98104265E+01   beta 2         0.35722825E+00  0.23974050E-01  0.14900621E+02   sigma-squared  0.14348760E+00  0.34889837E-01  0.41125901E+01   gamma          0.99999999E+00  0.20432057E-02  0.48942698E+03   mu             0.60957134E+00  0.96312207E-01  0.63291182E+01    eta is restricted to be zero log likelihood function =  -0.55888481E+02 LR test of the one-sided error =   0.12257630E+02 with number of restrictions = 2 [note that this statistic has a mixed chi-square distribution] number of iterations =     14 (maximum number of iterations set at :   100) number of cross-sections =    182 上图是我用frontier做的结果，用的是14个地区，13年的数据，谁能帮忙给解释下这个结果呀、，不胜感激