# Re: st: random draw of single variable, not whole data

 From Austin Nichols To statalist@hsphsun2.harvard.edu Subject Re: st: random draw of single variable, not whole data Date Thu, 26 Feb 2009 14:35:12 -0500

```Just for the sake of preserving threads:

clear
set obs 10
g x=rnormal()
g y = x[ceil(_N*uniform())]
list

On Thu, Feb 26, 2009 at 2:31 PM, Antoine Terracol
<terracol@univ-paris1.fr> wrote:
> You're correct.
>
> building on Jeph's solution:
>
> clear
> set obs 10
> g x=rnormal()
> g y=x[int(_N*uniform())+1]
> li
>
>
> Antoine
>
>
> Austin Nichols wrote:
>>
>> Antoine Terracol <terracol@univ-paris1.fr>:
>> Except the poster wanted resampling with replacement, so you need to
>> generate a random obs to draw from (for each obs) from the integers 1
>> to N (not simply randomize the order of obs).  Look in bsample.ado for
>> a "fast method for resample of size _N"
>>
>> On Thu, Feb 26, 2009 at 2:12 PM, Antoine Terracol
>> <terracol@univ-paris1.fr> wrote:
>>>
>>> In addition to -bsample- and -merge-, another solution is:
>>>
>>> clear
>>> set obs 10
>>> g x=rnormal()
>>> g rnd=uniform()
>>> egen rank=rank(rnd)
>>> g y=x[rank]
>>> li
>>> drop rank
>>>
>>>
>>> Antoine
>>>
>>> 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/
```