Talk:McNemar's test
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I don't think the given table fit the McNemar's test.
The test should be used in case of frequency counts on a dichotomic scale, with two measures on the same units (so the observations are dependents): in the article it's stated: dichotomic trait with matched pairs of subjects (that is the same). But matched pairs stands for tho measures on the same subjects: so the sex on somebody cannot fix (unless we want to know how many subjects change sex after having flown!).
The mis-understanding rely on the fact that in the article we talk about contingency table. The McNemar's test is not for 2x2 contingency table (with indipendent observations!) whereas it should be applied the Fisher's exact test or Chi squared test.
See the table in the italian wiki.
--Francesco R. 09:09, 9 December 2005 (UTC)
I agree. The table didn't show counts of matched pairs. I found the following statement to be confusing:
"Individuals without the disease are controls and individuals with the disease are cases. Within the cases and controls, individuals with the hypothesized disease gene are marked as positive for the presence of the gene and individuals without the gene are marked as negative."
into
The previous version (boys/girls, flown/not flown) before Cannin's last edit may have been better. I have exchanged the example with a typical drug testing scenario with before (control) and after conditions. I hope this is better.
--David Reitter 10 March 2006
