AW: st: sort of standardization

["Martin Weiss" <martin.weiss1@gmx.de>]

<> 

" local range=r(max)-r(min)+1"




Rich, what does the "+1" term do for the "range"? I took the definition in
my code from [R], page 204. Am I missing anything?





HTH
Martin


-----Ursprüngliche Nachricht-----
Von: owner-statalist@hsphsun2.harvard.edu
[mailto:owner-statalist@hsphsun2.harvard.edu] Im Auftrag von Richard
Goldstein
Gesendet: Mittwoch, 12. Mai 2010 16:40
An: statalist@hsphsun2.harvard.edu
Cc: Ginevra Biino
Betreff: Re: st: sort of standardization

if I understand correctly what you want, I would do the following within
a -foreach- loop:

summarize variable
calculate the range from r(min) and r(max)
divide the old variable by this calculated range inside a -gen-

e.g.,

foreach var of varlist .... {
qui su `var'
local range=r(max)-r(min)+1
gen `var'3=`var'/`range'
}

Rich

On 5/12/10 10:29 AM, Ginevra Biino wrote:
> Dear Statalist,
> I have to standardize many variables (in order to run PCA).
> Besides generating the n corresponding std(varname) vars, which I have
> already done, I also want to generate n new  variables obtained dividing
> each variable by its range. Can anybody help me?
> Ginevra
>  
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