Goodman (1979) proposed a class of diagonals-parameter symmetry models for square contingency tables with ordered categories, A simple version of that model is considered in which the log odds parameters have a linear pattern. The model is also a simple quasi-symmetry model. It fits well when...

In magazine advertisements for new drugs, it is common to see summary tables that compare the relative frequency of several side-effects for the drug and for a placebo, based on results from placebo-controlled clinical trials. The paper summarizes ways to conduct a global test of equality of the...

Cohen's (1960) kappa summarizes agreement between classifications of two fixed raters on a categorical scale. This note exhibits a simple quasi-symmetry model for which kappa contains all relevant information about the structure of agreement and disagreement.