[R] Can I use "mcnemar.test" for 3*3 tables (or is there a bug in the command?)

[Peter Dalgaard]

Charles C. Berry wrote:

> 
> The test mcnemar.test() constructs is one of symmetry, which is 
> equivalent to marginal homogenity in hierarchical log-linear models as I 
> recall from Bishop, Fienberg, and Holland's 1975 opus on count data.

Umm, er... Symmetry in the 3x3 table is a 3DF hypothesis, whereas 
marginal homogeneity has 2DF, so unless I'm missing a fine point in the 
requirement of "hierarchical log-linear", I'd say that one implies the 
other, but not the other way around.

E.g., you can easily check that the following two matrices have the same 
homogeneous margins, but only one is symmetric

3 2 1
2 3 2
1 2 3

3 1 2
3 3 1
0 3 3

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