Search Results - "Colombi, Roberto"

hmmm : An R Package for Hierarchical Multinomial Marginal Models by Colombi, Roberto, Giordano, Sabrina, Cazzaro, Manuela

“…In this paper we show how complete hierarchical multinomial marginal (HMM) models for categorical variables can be defined, estimated and tested using the R…”
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Markov switching stereotype logit models for longitudinal ordinal data affected by unobserved heterogeneity in responding behavior by Colombi, Roberto, Giordano, Sabrina

“…When asked to assess their opinion about attitudes or perceptions on Likert-scale, respondents often endorse the midpoint or extremes of the scale and agree or…”
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Determinants of transient and persistent hospital efficiency: The case of Italy by Colombi, Roberto, Martini, Gianmaria, Vittadini, Giorgio

“…Summary In this paper, we extend the 4‐random‐component closed skew‐normal stochastic frontier model by including exogenous determinants of hospital persistent…”
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Selection tests for possibly misspecified hierarchical multinomial marginal models by Colombi, Roberto

“…Hierarchical marginal models have been proposed for categorical data to overcome some limitations of the log-linear approach in modeling marginal…”
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Modeling different behaviors in disclosing risk perception by Colombi, Roberto, Giordano, Sabrina

“…In many fields, people are requested to express their level of awareness about some risk (mainly associated with health, environment, energy, etc.) by…”
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Likelihood-based tests for a class of misspecified finite mixture models for ordinal categorical data by Colombi, Roberto, Giordano, Sabrina

“…The main purpose of this paper is to apply likelihood-based hypothesis testing procedures to a class of latent variable models for ordinal responses that allow…”
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Hidden Markov models for longitudinal rating data with dynamic response styles by Colombi, Roberto, Giordano, Sabrina, Kateri, Maria

“…This work deals with the analysis of longitudinal ordinal responses. The novelty of the proposed approach is in modeling simultaneously the temporal dynamics…”
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Closed-skew normality in stochastic frontiers with individual effects and long/short-run efficiency by Colombi, Roberto, Kumbhakar, Subal C., Martini, Gianmaria, Vittadini, Giorgio

“…This paper considers the estimation of Kumbhakar et al. (J Prod Anal, doi:10.1007/s11123-012-0303-1, 2012) (KLH) four random components stochastic frontier…”
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Type II chain graph models for categorical data: A smooth subclass by NICOLUSSI, FEDERICA, COLOMBI, ROBERTO

“…The Probabilistic Graphical Models use graphs in order to represent the joint distribution of q variables. These models are useful for their ability to capture…”
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A class of mixture models for multidimensional ordinal data by Colombi, Roberto, Giordano, Sabrina

“…In rating surveys, people are requested to express preferences on several aspects related to a topic by selecting a category in an ordered scale. For such…”
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A Rating Scale Mixture Model to Account for the Tendency to Middle and Extreme Categories by Colombi, Roberto, Giordano, Sabrina, Tutz, Gerhard

“…A mixture of logit models is proposed that discriminates between responses to rating questions that are affected by a tendency to prefer middle or extremes of…”
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Hierarchical marginal models with latent uncertainty by Colombi, Roberto, Giordano, Sabrina, Gottard, Anna, Iannario, Maria

“…In responding to a rating question, an individual may give answers either according to his/her knowledge/awareness or to his/her level of…”
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Marginal Nested Interactions for Contingency Tables by Cazzaro, Manuela, Colombi, Roberto

“…We introduce a new definition of generalized marginal interactions, called marginal nested interactions, which includes baseline, local, continuation and…”
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Discussion of “The class of CUB models: statistical foundations, inferential issues and empirical evidence” by Colombi, Roberto, Giordano, Sabrina, Gottard, Anna

“…We contribute to the discussion of the paper of Piccolo and Simone by examining some issues concerning the multivariate extension of CUB and GEM models…”
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Monotone dependence in graphical models for multivariate Markov chains by Colombi, Roberto, Giordano, Sabrina

“…We show that a deeper insight into the relations among marginal processes of a multivariate Markov chain can be gained by testing hypotheses of Granger…”
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Latent class models for ecological inference on voters transitions by Colombi, Roberto, Forcina, Antonio

“…This paper introduces some new models of ecological inference within the context of estimation of voter transitions across elections. In particular, we assume…”
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AN EXTENDED CLASS OF MARGINAL LINK FUNCTIONS FOR MODELLING CONTINGENCY TABLES BY EQUALITY AND INEQUALITY CONSTRAINTS by Bartolucci, Francesco, Colombi, Roberto, Forcina, Antonio

“…We extend Bergsma and Rudas (2002)'s hierarchical complete marginal parameterization to allow for logits and higher order effects of global and continuation…”
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Testing lumpability for marginal discrete hidden Markov models by Colombi, Roberto, Giordano, Sabrina

“…When some states of a Markov chain are aggregated (or lumped) and the new process, with lumped states, inherits the Markov property, the original chain is said…”
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Risk of persistence after electrosurgical excision of cervical intraepithelial neoplasia by Prun, Eugenio Solima/Allegra Barbasetti di, Prun, Allegra Barbasetti di, Messori, Pietro, Buratti, Elisabetta, Colombi, Roberto, Alabiso, Giulia, Busacca, Mauro

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Some conditional independencies in bivariate categorical time series by Roberto Colombi, Sabrina Giordano

“…In this work we consider two time series of categorical data as a bivariate Markov chain. The markovianity assumption allows us to simplify some conditional…”
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