The number of 2 × c tables with given margins Øyvind
نویسندگان
چکیده
We provide an elementary proof of a formula for the number of possible 2× c contingency tables with given row and column sums. Further, we show that the number of r×c contingency tables with given row sums is maximal as a function of column sums when column sums are as equal as possible. If only the sum of all table entries is given, the number of tables is maximal when also row sums are as equal as possible. The knowledge of those numbers is useful for determining which method to use for statistical testing of association in a contingency table.
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