On Wed, Mar 4, 2009 at 2:48 AM, Daniel Nordlund <djnordl...@verizon.net> wrote: >> -----Original Message----- >> From: r-help-boun...@r-project.org >> [mailto:r-help-boun...@r-project.org] On Behalf Of CB >> Sent: Tuesday, March 03, 2009 10:05 PM >> To: David Winsemius >> Cc: r-help@r-project.org >> Subject: Re: [R] How to generate fake population (ie. not >> sample) data? >> >> My understanding is that rnorm(n, x, s) will give me an n-sized sample >> from an (x, s) normal distribution. So the vector returned will have a >> mean from the sampling distribution of the mean. But what I want is a >> set of n numbers literally with a mean of x and sd of s. >> >> I am at the very beginning of my R journey, so my apologies if this is >> a particularly naive enquiry. >> >> 2009/3/4 David Winsemius <dwinsem...@comcast.net>: >> > In what ways is rnorm not a satisfactory answer? >> > >> > -- >> > David Winsemius >> > >> > On Mar 3, 2009, at 9:33 PM, CB wrote: >> > >> >> This seems like it should be obvious, but searches I've >> tried all come >> >> up with rnorm etc. >> >> >> >> Is there a way of generating normally-distributed 'population' data >> >> with known parameters? >> >> >> >> Cheers, CB. >> >> > > Something like this may help get you started. > > std.pop <- function(x,mu,stdev){ > ((x-mean(x))/sd(x)*stdev)+mu > }
Note the scale function, i.e. the above can also be written: stdev * scale(x) + mu > > population <- std.pop(rnorm(1000),10,5) > > Hope this is helpful, > > Dan > > Daniel Nordlund > Bothell, WA USA > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
