rictan 发表于 2013-6-13 23:19 
不好意思,我初学不太明白。能否具体说明呢?你建议是用stata做么?
mergeall is a user-written Stata command, you have to install it before you can use it. Type the following in your Stata "Command Window" :
findit mergeall
Follow the instructions to find and install it, then in the "Command Window", type the follow to know how to use it:
Help mergeall