DID estimation

[jeffrey bosah]

hello everyone, how can I treat the problem if I see an error years not nested in countryid
or countryid not a control.

[Øyvind Snilsberg]

I think you want -cluster(countryid)- instead of -cluster(year)-
What command did you use?

[jeffrey bosah]

so i am trying to do a DID estimation, these were my commands
xtdidregress (lnFDI lnGDP) (post), group(country_id) time(years)

[jeffrey bosah]

the issue i am seeing is with group when i try, either years is not nested in countryid
when i encode countryid it then says none of the group defined by new countryid is a control