Hello Jumlong, I'm not sure whether by '100 records' you mean a vector of 100 values or a matrix / data.frame of 100 rows.
For a vector or matrix X you can do this: X[ sample( length(X), 5 ) ] <- NA For a data.frame X you could do this: X[ sample( nrow(X), 5 ), sample( ncol(X), 5) ] <- NA Hope this helps, Michael On 12 October 2010 13:14, Jumlong Vongprasert <jumlong.u...@gmail.com> wrote: > Dear all > I want to create dataset with MCAR type from my dataset. > I have my dataset with 100 records, and I want to create dataset from this > dataset to missing 5 records. > How I can do it. > THX > Jumlong > > -- > Jumlong Vongprasert > Institute of Research and Development > Ubon Ratchathani Rajabhat University > Ubon Ratchathani > THAILAND > 34000 > > [[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. > ______________________________________________ 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.
