stata基础求助

海底浮云 发表于 2014-3-23 16:20
Try this please:
sort firmid year
xtset firmid year

还是没出来呀。数据我查过好几遍了，应该不是数据本身的问题。

You should encode the firmid to numeric format and this can be achieved with the following command:
encode firmid , generate(firmidn)

then use firmidn instead of  firmid  and declare the panel data again by
sort firmid year
xtset firmid year

You should be patient and solve the problem via www.google.com next time.

Good luck!

海底浮云 发表于 2014-3-23 16:40
You should encode the firmid to numeric format and this can be achieved with the following command:
...

Thanks a lot！^_^