Abstract: With two judges and a two-point rating scale, the test statistic for Kappa is the same as Pearson's chi-square statistic applied to the 2 × 2 table of paired observations. This equivalence allows a quick test of the null hypothesis of no agreement, as Pearson's chisquare statistic is much less cumbersome to compute than the Kappa statistic and its variance. A simple formula for the null hypothesis variance is also derived.
scite is a Brooklyn-based startup that helps researchers better discover and evaluate scientific articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by researchers from dozens of countries and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.