Iannario, Maria Creator Faculty rosaria.simone@unina.it Simone, Rosaria Creator MATH / Applied Mathematics Illinois Institute of Technology Affiliated department Ordinal data Gröbner basis Method of moments Uncertainty Overdispersion 2017 2017-12-26 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. Article

born digital application/pdf en https://doi.org/10.18409/jas.v8i2.60 8.2 Open Access eng http://hdl.handle.net/10560/islandora:1007799