Getting all possible contingency tables

Christopher:

Don't do this!

 If I understand you correctly, you want FIsher's exact test. This is
already available in R, using far smarter algorithms then you would. See:

?fisher.test

-- Bert

On Sat, Dec 1, 2012 at 5:48 AM, Christofer Bogaso
<bogaso.christofer at gmail.com <mailto:bogaso.christofer at gmail.com>> wrote:

    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
            <mailto:bogaso.christofer at gmail.com>
            Sent: Sat, 01 Dec 2012 18:10:15 +0545
            To: r-help at r-project.org <mailto: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,