Re: AW: st: sort of standardization

[Richard Goldstein <richgold@ix.netcom.com>]

Martin,

look at it this way -- if my min is 1 and my max is 10, then the range
is 10 (it seems to me), not 9 -- i.e., I think of the range as the min
to the max *inclusive* of each endpoint; StataCorp apparently disagrees ;-)

Rich

On 5/12/10 10:46 AM, Martin Weiss wrote:
> 
> <> 
> 
> " 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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