bootstrap r(ind_eff) r(dir_eff),reps(1000) : sgmediation Ana , mv( DA ) iv( Sd ) cv( Size Roa Lev Itang Grow Horizon Holder TobinQ Cr Soe Age )
estat bootstrap,percentile bc
我在论坛里看到这个命令 bootstrap r(ind_eff) r(dir_eff), reps(1000): sgmediationy, mv( m ) iv( x ) cv( controls )运行显示'r(ind_eff)' evaluated to missing in full sample是什么意思呢