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From |
Jeph Herrin <junk@spandrel.net> |

To |
statalist@hsphsun2.harvard.edu |

Subject |
Re: AW: st: random draw of single variable, not whole data |

Date |
Thu, 26 Feb 2009 14:41:29 -0500 |

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: owner-statalist@hsphsun2.harvard.edu [mailto:owner-statalist@hsphsun2.harvard.edu] Im Auftrag von Jeph Herrin Gesendet: Donnerstag, 26. Februar 2009 20:20 An: statalist@hsphsun2.harvard.edu 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 itinto another variable yi.e. if x 1 2 3 4 5 then y could be, for instance y 3 5 3 2 4all numbers in y are randomly drawn from x. how is it possible toconstruct 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/

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**Follow-Ups**:**AW: AW: st: random draw of single variable, not whole data***From:*"Martin Weiss" <martin.weiss1@gmx.de>

**References**:**st: random draw of single variable, not whole data***From:*Florian Wakolbinger <wakolbinger@drei-e.at>

**Re: st: random draw of single variable, not whole data***From:*Jeph Herrin <junk@spandrel.net>

**AW: st: random draw of single variable, not whole data***From:*"Martin Weiss" <martin.weiss1@gmx.de>

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