[R] Questions about generating samples in R

[Mark Na]

Further to Alexander's question ... could anyone provide assistance
with random stratified sampling? Let's say we have Alex's dataframe
and we want to stratify the random selection by group membership
(which is contained in one of the eight columns).

We might want to randomly select:

1) a constant number (e.g., 5) of rows from each group, or
2) a percentage (e.g. 10%) of rows from each group resulting in groups
being represented proportionally in the sample (with respect to the
population).

I am aware of stratsrs but this function does not seem to allow the
second of the above two options.

Any ideas how to achieve this in R?

Thanks, Mark



On 11/26/06, Alexander Geisler <alexander.geisler at gmail.com> wrote:
> Hello!
>
> I have a data set with 8 columns and in about 5000 rows. What I want to
> do is to generate samples of this data set.
>
> Samples of a special size, as example 200.
>
> What is the easiest way to do this? No special things are needed, only
> the random selection of 200 rows of the data set.
>
> Thanks
> Alex
>
> --
> Alexander Geisler * Kaltenbach 151 * A-6272 Kaltenbach
> email: alexander.geisler at gmx.at | alexander.geisler at gmail.com
> phone: +43 650 / 811 61 90 | skpye: al1405ex
>
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