您好,购买了您的xthreg2报错方案并把文件lxthreg.mlib放到指定ado文件中,但是依旧报错,该如何处理?There exist time-invariant individual(s) (maybe only one obs): oversearev citydf Dig
xtdev2(): 3301 subscript invalid
thestm2(): - function returned error
<istmt>: - function returned error
我用的STATA17