Some considerations on VCUB models

CUB models are useful for studying ordinal data in rating surveys. The response probabilities are modelled as a convex combination of a shifted Binomial and a discrete Uniform distribution, to capture respondent psychological behaviour of being only partially able to quantify his/her feeling toward a specific item. A recent extension of CUB models, called the VCUB model, replaces the Uniform component with a variety of distributions, allowing for a more flexible description of respondent uncertainty. The comparison of different options can be interesting also from a psychological point of view. This work studies the necessity of multiple comparison adjustments, whenever several specifications seem adequate.