Hi,

I have panel data and defined my variables accordingly:
xtset id q_date,q
if i want to standardize a variable by taking (v1-mean of v1)/(standard deviation of v1), can i do it as :

Code:
egen zv1=std(v1)
?? or should i standardize v1 for for each company(id)? in other words do we standardize at the aggregate level for all companies or for each company alone? if it is the latter how can i modify the codes?

thanks