Re sampling from an ECDF

Say F_n is my ecdf, generated from my sample x.
With sample(x, 2000, replace = TRUE) I get a uniformly distributed sample
from x.

Which is not the same as uniformly from unique(x).
But I need a (re)sample, which is F_n distributed.
Now I'm confused, if that makes a difference or not...
Just recognize that
tab <- table(x)
sample( as.numeric(names(tab)), 10, prob=tab, repl=TRUE )
and
sample( x, 10 , repl=TRUE )
are both samples from the same population, and your confusion will abate.

:-)

Chuck
Regards,
Martin

Dimitris Rizopoulos-4 wrote:
say 'x' is your sample, then try

sample(x, 2000, replace = TRUE)

I hope it helps.

Best,
Dimitris
--
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus Medical Center

Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands
Tel: +31/(0)10/7043478
Fax: +31/(0)10/7043014

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______________________________________________
R-help at r-project.org mailing list
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Charles C. Berry                            (858) 534-2098
                                             Dept of Family/Preventive Medicine
E mailto:cberry at tajo.ucsd.edu	            UC San Diego
http://famprevmed.ucsd.edu/faculty/cberry/  La Jolla, San Diego 92093-0901

Re sampling from an ECDF

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