Hello,

I am reading my friend's STATA code, which is to append several data file.

But before append files, she did the following step, which she notes as "change variable type so that we can append".

save "$folder/data_panel/2004panel.dta", replace
use "$folder/data_panel/2005panel.dta", clear
tostring CIIU4 REGION, replace

I do not understand why do we need to change variable type, by using "tostring" ?Actually all the files used for appending included identical variables.

If someone has an idea, plz kindly help me.

Thank you in advance!