我用的是stata17 MP版本，做did安慰剂检验，使用permute命令，报错提示program did not found，问下是怎么回事呢？<br>
在执行permute did beta = _b[did] se= _se[did] df = e(df_r), reps(500) rseed(123) saving("simulations.dta"): reghdfe y did, absorb(country year) vce(robust)命令，报错program did not found<br>