Mixture models for rating data: the method of moments via Groebner bases
A recent thread of research in ordinal data analysis involves a class of mixture models that designs the responses as the combination of the two main aspects driving the decision pro- cess: a feeling and an uncertainty components. This novel paradigm has been proven flexible to account also for overdispersion. In this context, Groebner bases are exploited to estimate model parameters by implementing the method of moments. In order to strengthen the validity of the moment procedure so derived, alternatives parameter estimates are tested by means of a simulation experiment. Results show that the moment estimators are satisfactory per se, and that they significantly reduce the bias and perform more efficiently than others when they are set as starting values for the Expectation-Maximization algorithm.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Upon submission, authors agree with the following Article Submission Agreement. Once the papers are published, authors are required to use the DOI link provided on all websites and arXiv postings of their paper.
As this is an open access journal, all articles have a creative commons license.