前面部分的程序是这个,do 就是我的自变量
clear
set matsize 900
use "C:\Users\THINKPAD\Desktop\match\DO.dta"
local N=_N
mkmat stkcd year indcd do size lev,mat(DO)
capture postclose match
postfile match stkcd year do match_group using "C:\Users\THINKPAD\Desktop\match\mymatch.dta",replace