R help - Jun 2014 - Sample all possible contingency tables both margin fixed

Hi,

I am interested in generating all possible contingency table (2 by 2) with fixed
row margins and column margins. Can anyone help me.

Best regards,
Tahira 
	[[alternative HTML version deleted]]

On Tue, Jun 24, 2014 at 10:41 AM, Tahira Jamil <tahjamil at gmail.com>
wrote:
> Hi,
>
> I am interested in generating all possible contingency table (2 by 2) with
fixed row margins and column margins. Can anyone help me.
>
If the reason you want this is to sample them then r2dtable can do
that directly.

On 24 Jun 2014, at 16:41 , Tahira Jamil <tahjamil at gmail.com> wrote:
> Hi,
> 
> I am interested in generating all possible contingency table (2 by 2) with
fixed row margins and column margins. Can anyone help me.
> 

It's pretty easy, just find one compatible solution and add or subtract

1 -1
-1  1

until one of the numbers would go negative. Or put differently, if you know one
entry, you know the other three, so it is just a matter of working out the range
of (say) possible top-left entries.

With more than 2x2 tables it is much harder, but fisher.test() does it
internally.

-pd

> Best regards,
> Tahira 
> 	[[alternative HTML version deleted]]
> 
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