sungmoo 发表于 2012-3-8 18:07 
*不知道你的i具体取何值,只以一种情况为例(在do-file中do以下):
clear
非常感谢,我用你的写的程序做了一下
出现如下结果
initial: log likelihood = -<inf> (could not be evaluated)
feasible: log likelihood = -9.9588383
rescale: log likelihood = -9.9519595
rescale eq: log likelihood = -9.9393753
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 0: log likelihood = -9.9393753
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 1: log likelihood = -9.9393753
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 2: log likelihood = -9.9393753
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 3: log likelihood = -9.9393753
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 4: log likelihood = -9.9393753
Iteration 5: log likelihood = -9.9393753 (not concave)