I am running a fixed effects regression and am getting the following error:
fixed_effects <- plm(GNI ~ lag(GNI) + imposition + ExpImp + democ,
data = sanctions_data6, index = c("country", "sanctions_period"), model =
"within", effect = "twoways")
duplicate couples (time-id)
Error in pdim.default(index[[1]], index[[2]]) :
I am aware that it means that i have duplicate time periods for the same observations. However the whole observations are not duplicates of each other as they represent different types of sanctions imposed.
country sanctions_period sanction_type
(chr) (chr) (int)
1 Afghanistan 1995-2002 4
2 Afghanistan 1995-2002 7
3 Afghanistan 1995-2002 NA
How can i get around this problem and run a regression in order to see the results? Thanks!