SpencerMeng 发表于 2015-4-7 19:43 
是bys,而不是by。
bys是bysort的缩写。

还是不行呢 by group: egen M = mean (Yretwd14)
unknown egen function mean()
r(133);
. by group: egenM=mean(Yretwd14)
unrecognized command: egenM
r(199);
. bys group: egen m=mean(Yretwd14)
unknown egen function mean()
r(133);
. bys group: egen m=mean(Yretwd14)
unknown egen function mean()
r(133);
. bys group: egen m=mean(yretwd14)
unknown egen function mean()
r(133);
. by group: egen M = mean (yretwd14)
unknown egen function mean()
r(133);
. bys group: egen m=mean(Yretwd14)
unknown egen function mean()
r(133);
. bysort group: egen m=mean(Yretwd14)
unknown egen function mean()
r(133);
怎样都是错的