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Re: AW: st: random draw of single variable, not whole data
You're right about the missings; I didn't get any but
I could have. Maybe
gen y = x[ceil(_N*uniform())]
as long as uniform() never returns precisely 0, which I've
never seen - can it?
But certainly there's no reference to the values that x takes;
a random observation number is generated in (1,...,_N) and y is
set equal to that observation on x. So yes, it handles whatever
x looks like, I'm merely sampling from the list of observation
numbers.
J
Martin Weiss wrote:
> <>
>
>
> Your "with replacement" method leads to missings every now and then. Apart
> from that, if Florian had an irregularly spaced list of numbers to sample
> from, which also need not be integers, would your method be capable of
> handling that?
>
>
>
> HTH
> Martin
>
>
> -----Ursprüngliche Nachricht-----
> Von: [email protected]
> [mailto:[email protected]] Im Auftrag von Jeph Herrin
> Gesendet: Donnerstag, 26. Februar 2009 20:20
> An: [email protected]
> Betreff: Re: st: random draw of single variable, not whole data
>
>
> It's not clear if you want sampling with or without replacement.
>
> With replacement:
>
> gen y = x[round(_N*uniform(),1)+1]
>
> without replacement:
>
> egen index=rank(uniform())
> gen y = x[index]
>
> hth,
> Jeph
>
>
> Florian Wakolbinger wrote:
>> Dear all,
>>
>> is it possible to randomly draw numbers out of a variable x and write it
>> into another variable y
>>
>> i.e. if
>>
>> x
>> 1
>> 2
>> 3
>> 4
>> 5
>>
>> then y could be, for instance
>>
>> y
>> 3
>> 5
>> 3
>> 2
>> 4
>>
>> all numbers in y are randomly drawn from x. how is it possible to
>> construct such a variable y in stata?
>>
>> thanks, and kind regards
>> florian
>>
>> *
>> * 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/
>
*
* 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/