McNemar Test

It is often of interest to examine changes in the dichotomous categorical responses taken from subjects before and then after some treatment condition is imposed (i.e., evaluating repeated measurements of the same subjects using them as their own controls). In 1947, psychologist Quinn McNemar developed a simple and valuable technique for comparing differences between the proportions in the responses before and after.

McNemar’s procedure has enjoyed widespread usage in both behavioral and medical research and some attention in business, particularly with applications in advertising or marketing research, wherein it may be desirable to evaluate the significance of changes in attitudes and opinions as observed in brand loyalty and switching patterns. In this same context, McNemar’s procedure may be employed to assess the results of a two-candidate ...