[R] randomisation

[francoisromain@free.fr]

Selon Yann Clough <y.clough at NS1.uaoe.gwdg.de>:

> Dear useRs
>
> I am looking for a way to randomise the values within a matrix:
> the conditions are that the sums of the rows and the sums of the columns
> should
> remain the same as in the original matrix.
>
> Any help would be appreciated
> Cheers
>
> Yann
>
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Hello, your question makes me think about what does the chisq.test function with
simulate.p.value = T, maybe that could help to look what is done there.

The help page of chisq.test points to that reference wich seems quite like what
you are looking for :

Patefield, W. M. (1981) Algorithm AS159. An efficient method of generating r x c
tables with given row and column totals. Applied Statistics 30, 91-97.


Romain.