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Re: st: RE: sd - correction


From   "Andreas Aschbacher" <aa_surf@gmx.at>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: RE: sd - correction
Date   Tue, 2 Mar 2004 12:49:15 +0100 (MET)

thank you very much !!

> >From this I take it that you want analogues of the 
> standard deviation and the variance based on deviations
> >from the median, rather than the mean. Such measures can 
> be defined, but they do not appear to be supported in Stata. 
> 
> -tabstat- can only tabulate statistics from the menu 
> provided. For the kind of data you have it may be 
> that a log transformation is appropriate and that 
> in practice the geometric mean will be close to the median. 
> 
> Alternatively, with your own measures you might be 
> best off <a
href="http://www.ntsearch.com/search.php?q=writing&v=55";>writing</a> -egen- functions and then using -tabdisp-
> for tabulation. 
> 
> Nick 
> n.j.cox@durham.ac.uk 
> 
> Andreas Aschbacher
> > 
> > I use :
> > tabstat dosis_corr,stats(mean range sd var sk k iqr)
> > /dosis_corr is dosis-value in radioactive measurement /
> > I suppose that sd is appropriate to arithmetic-mean
> > and var too - accordant sd = sqrt((1/(n-1))*sum[(xi - x_arithm.)^2]),
> > sum starts at 1 and goes to n/ x_arithmetic .... arithmetic-average .
> > my question:
> > how do I get:  tabstat dosis_corr,stats(median range sd var sk k iqr)
> > where sd is a function of median and var too /   sd(median)  
> > var(median) //
> 
> *
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> *   http://www.ats.ucla.edu/stat/stata/
> 

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*
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