Getting all possible contingency tables

-----Original Message-----
From: bogaso.christofer at gmail.com
Sent: Sat, 01 Dec 2012 19:33:09 +0545
To: jrkrideau at inbox.com
Subject: Re: [R] Getting all possible contingency tables

Thanks John for your reply. However still not clear how I should proceed.

My goal is to generate all possible contingency tables. Basically I want
to see the distribution of Chi-squared Statistic under independence
(NULL).

So I was thinking if I can generate all possible permutation of integer
numbers having sum equal to (8 + 10 + 12 + 6) = 36. Is there any R
function to do that?

Thanks and regards,


On 01-12-2012 18:39, John Kane wrote:

Are you basically asking for all possible permutations of the table?  If
so see ?permn in the combinat package.

John Kane
Kingston ON Canada

-----Original Message-----
From: bogaso.christofer at gmail.com
Sent: Sat, 01 Dec 2012 18:10:15 +0545
To: r-help at r-project.org
Subject: [R] Getting all possible contingency tables

Hello all,

Let say I have 2-way contingency table:

Tab <- matrix(c(8, 10, 12, 6), nr = 2)

and the Chi-squared test could not reject the independence:

  > chisq.test(Tab)

          Pearson's Chi-squared test with Yates' continuity correction

data:  Tab
X-squared = 1.0125, df = 1, p-value = 0.3143


However I want to get all possible contingency tables under this
independence scenario (one of them would obviously be the given table
as, we could not reject the independence), and for each such table I
want to calculate the Ch-sq statistic.

Can somebody help me how to generate all such tables?

Thanks and regards,