Modelling and Analysing Paired Ranking Data

Two models for paired rankings are presented. They describe two different ways in which a post-ranking is related to its pre-ranking for each case (or subject). These models are compared to regression models in order to help motivate their forms. Analysis of paired ranking data is considered in the light of testing for that type of departure from a null model that corresponds to either of the proposed models. The procedure suggested uses a bootstrap method to ascertain the strength of the departure from the null model, and helps one to decide which departure is more strongly indicated. Some analyses of simulated test data sets are described, as well as the analysis of data due to Rogers [7] which is also analysed in Critchlow and Verducci [3].