Hello,

I am newbie in Stata and I have a problem with stata when I try to declare If condition.

In my DB, I have "country" variable which has "Germany" values but when I run the regression:

"oprobit adl iadl depression_scale chronicw2 if country==Germany". It said that "Germany not found"
or
" oprobit adl iadl depression_scale if "country"=="Germany" ". It said that "no observations"

How can I fix it?

Thank you