Statalist


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: Re: dataset generation


From   Nikolaos Pandis <npandis@yahoo.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: Re: dataset generation
Date   Sun, 24 May 2009 03:31:11 -0700 (PDT)

many thanks

--- On Sun, 5/24/09, Martin Weiss <martin.weiss1@gmx.de> wrote:

> From: Martin Weiss <martin.weiss1@gmx.de>
> Subject: st: Re: dataset generation
> To: statalist@hsphsun2.harvard.edu
> Date: Sunday, May 24, 2009, 1:25 PM
> <>
> 
> Nikolaos might also like to acquaint himself with the
> -drawnorm- command:
> 
> ***
> drop _all
> drawnorm x y, n(20) means(15 18) /*
> */corr(1, 0 \ 0, 1) sds(4 6) /*
> */cstorage(full) seed(41322)
> su
> ***
> 
> Two problems are apparent in his request:
> 
> The small sample size makes deviations from his desired
> values for the mean 
> and standard deviation very likely. If he is willing to
> increase the sample 
> size, this problem will (almost) vanish.
> 
> The reason people recommend the normal distribution for
> this kind of problem 
> is that you can change the mean and sd to the values you
> like. Note that for 
> some of the random number functions in -help
> random_number_functions-, the 
> mean and variance are functions of each other. In the case
> of the poisson, 
> they are identical, making it harder to make them diverge
> in the way 
> Nikolaos wants them to....
> 
> 
> HTH
> Martin
> _______________________
> ----- Original Message ----- 
> From: "Nikolaos Pandis" <npandis@yahoo.com>
> To: <statalist@hsphsun2.harvard.edu>
> Sent: Sunday, May 24, 2009 9:15 AM
> Subject: st: dataset generation
> 
> 
> > Hi,
> >
> > I would like to ask for help in the following:
> >
> > I would like to generate a small dataset with  2
> columns:
> > column 1: observations 20, mean= 15, sd= 4
> > column 2: observations 20, mean=18, sd=6
> >
> > How would I do that?
> >
> > Many thanks in advance.
> >
> > Nick
> >
> >
> >
> > *
> > *   For searches and help try:
> > *   http://www.stata.com/help.cgi?search
> > *   http://www.stata.com/support/statalist/faq
> > *   http://www.ats.ucla.edu/stat/stata/
> > 
> 
> *
> *   For searches and help try:
> *   http://www.stata.com/help.cgi?search
> *   http://www.stata.com/support/statalist/faq
> *   http://www.ats.ucla.edu/stat/stata/
> 


      

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index