no observation error (2000) after entering control variables.

[parry madani]

Hi, I'm working on mexico pension program and at primary steps, when I want to estimate impact of program by linear regression it works but when I enter my control variables I get below results in the picture, (no observation). I read in Other topics that it can be because of string variables and omitted those but still get same error. for information I have missing data if it is a case, I read in other topic that maybe missing data can be an issue but I don't know how to resolve it. thanks.

[Nick Cox]

su spending_doc time $controls id_loc

will tell you how many non-missing values you have for each, but you need observations in which all variables are non-missing -- and it seems you have none.

[parry madani]

Thanks, I ran the command and it had a good information on the results and as you said it shows non of my control variables have full set of observation. Can I put 0 instead of missed data? does it cause an intervention error in original data set?

[parry madani]

i even tried use looping command as it was suggested in other topic but it gives same error.
. foreach x of global controls {
2.
. describe `x'
3.
. reg `x' spending_dec treatment $controls, cl(id_loc)
4.
. }

[Nick Cox]

Missing means zero only if missing means zero!

[parry madani]

Thanks Nick, then this option did not approved as well and I should ignore it.