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.ubru at 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
>
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