A comparison of approaches to the analysis of longitudinal categoric data


SSRC Fellow in Statistical Problems of Longitudinal Studies, Department of Statistics and Computing, University of Loudon Institute of Education, 20 Bedford Way, London WC1H 0AL.


Marascuilo & Serlin (1979) discuss the problem of measuring relative change for a dichotomous variable and suggest ways of testing for the statistical significance of such changes. This article considers alternatives to the non-parametric approach adopted by Marascuilo & Serlin, alternatives which emphasize statistical models and which can be extended to all types of longitudinal categoric data. The models are fitted to the data presented by Marascuilo & Serlin, the results are compared and the advantages and disadvantages of the various approaches are discussed.