Hi, On Thu, Apr 21, 2011 at 8:18 PM, Penny Bilton <pennybil...@xnet.co.nz> wrote: > I am using /set.seed()/ before the /sample/ function. > > How does the length of the argument of /set.seed()/ and order of the > digits affect how the sampling is carried out?
You can use set.seed() to specify a particular seed so that while pseudo-random numbers are sampled, you can repeat it. For example: set.seed(10) rnorm(10) set.seed(10) rnorm(10) > > Specifically, I have used set.seed(123456789). Will this configuration > give me a genuinely random sampling?? You will never get truly random sampling from a computer algorithm, but it is darn close and more than adequate in the majority of cases. 123456789 is just a length 1 vector containing the number 123456789, not 9 separate numbers. Google will be able to give you a lot of information on pseudo-random number algorithms as well as the concept of "seeds". Also see ?set.seed Cheers, Josh > > > Thank you in anticipation. > > Penny. > > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > -- Joshua Wiley Ph.D. Student, Health Psychology University of California, Los Angeles http://www.joshuawiley.com/ ______________________________________________ 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.
