Inference for cub models: A program in R

An alternative approach has been proposed for the analysis and the modelling of ordinal data: it is based on the psychological process by which a respondent expresses his/her evaluation about the item with an inherent indecision. This class of models has been developed with many variants and it is now indicated as CUB models. The purpose of this paper is to introduce users to the version 4.0 of a program, written in the R statistical environment, to make effective applications of CUB models and variants by exploiting their capabilities both from computational and graphical points of view. After a specification of the different structures, the basic commands are presented with some examples. Generalizations and extensions of the standard models are also mentioned. For a more extensive study a bibliographic note concludes the paper.