What does McNemar's test do?

hard

Answer

$Paired categorical (usually binary) test.$
$Compares proportions in matched pairs.$
${\chi}^{2}\; = \;(b\; - \;c)^{2}\; / \;(b\; + \;c)$
$Uses: classifier comparison on the same test set (does model A get more test items right than model B?), before / after intervention on the same subjects.$

Check yourself — multiple choice

Independent categorical
Paired binary test on discordant pairs (b, c) → $(b - c)^{2} / (b + c)$ ~ ${\chi}^{2}$ ; used for classifier comparison on shared test set
Same as chi-square independence
Only continuous

McNemar: paired binary test on discordant pairs; classifier comparison on shared test set.

#hypothesis-testing#non-parametric

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