ABSTRACT
The number of coefficients for rater agreement is large. However, the number of coefficients that is actually used in empirical research is small. The present section discusses five of the more frequently used coefficients. The first is Cohens, one of the most widely employed coefficients in the social sciences, is a coefficient for nominal level variables. The second and the third coefficients are variants of. The second coefficient, weighted, allows the statistical analyst to place differential weights on discrepant ratings. This coefficient requires ordinal rating scales. The third coefficient is Brennan and Predigers n, a variant of that uses a different chance model than the original. The fourth coefficient is raw agreement which expresses the degree of agreement as percentage of judgements in which raters agree. The fifth coefficient discussed here is Kendalls W. This coefficient is defined for ordinal variables.
