You can also use the mvtnorm package to simulate from multivariate normal.
See this example:
http://tolstoy.newcastle.edu.au/R/e11/help/10/08/5851.html

Kevin



On Wed, Dec 4, 2013 at 11:12 AM, alessandro <moskante@gmail.com> wrote:

> Hi Fiona,
>
> I think you can use the function rmronm form the package mnormt to
> simulate from a multivariate normal distribution with a given
> variance-covariance matrix. In case, I wrote a function for simulating a
> dataset with binary response variable, you can find it here:
>
> http://mixedpsychophysics.wordpress.com
>
> best
> Alessandro Moscatelli
>
> PS: for the moment, the some of the functions in the MERpsychophysics code
> are not compatible with lme4.1 - I hope I will upload the new code version
> in max 20 days…
>
> Il giorno 04/dic/2013, alle ore 17:48,
> r-sig-mixed-models-request@r-project.org ha scritto:
>
> > simulating datasets for mixed model analysis
>
>
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>
>
> _______________________________________________
> R-sig-mixed-models@r-project.org mailing list
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>
>


-- 
Kevin Wright

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