st: the use of loop function in Stata

[Rosie Chen <jiarongchen2002@yahoo.com>]

Dear all, this is the first time I use loop function combined with global macro, and I got an error message of ""invalid name" after running the syntax below. Could any of you help identity where the problem is? Thank you very much. 


***I have lp1, lp2, lp3, and lp4, and would like to do the same analysis (within the loop) on each of the lp variables. 
global lp "lp*" 
display "$lp"

foreach var of varlist $lp{

    histogram 'var',  by(AI4, col(1))
    sum 'var'
    egen std'var'= sd('var')
    gen sds'var'=0.2*std'var'
    bysort AI4: sum 'var'
    bysort AI4: egen mins'var'=min('var')
    egen min'var'=max(mins'var')
    bysort AI4: egen maxs'var'=max('var')
    egen max'var'=min(maxs'var')
    gen insamp'var'= ('var'>= (min'var'- sds'var') & 'var'<= max'var'+ sds'var')
}


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