The CUB model is a mixture distribution recently proposed in literature for modelling ordinal data. The CUB parameters may be related to explanatory variables describing the raters or the object of evaluation. Although various methodological aspects of this class of models have been investigated, the problem of multivariate ordinal data representation is still open. In this article the Plackett distribution is used in order to construct a bivariate distribution from CUB margins. Furthermore, the model is extended so that the effect of rater characteristics on their stated preferences is included.