Hi,
this is my first time using Stata.
I would like to include an interaction term in my model:

Code:
egen voc = group(vis)
Code:
xtreg foreign_revenues state_dom##voc state_min##voc log_age log_asset log_gdp_capita i.sector i.year, robust
where state_dom and state_min are dummy variables and voc is 4 different groups.

Can anyone tell me how to implement the same xtreg function manually creating interaction term instead of ##?

Thanks very much