Zobrazeno 1 - 10
of 39
pro vyhledávání: '"Roberto Colombi"'
Publikováno v:
Journal of Statistical Software, Vol 59, Iss 1, Pp 1-25 (2014)
In this paper we show how complete hierarchical multinomial marginal (HMM) models for categorical variables can be defined, estimated and tested using the R package hmmm. Models involving equality and inequality constraints on marginal parameters are
Externí odkaz:
https://doaj.org/article/69d086ba65ee496ab241e470dad3b29a
Autor:
Roberto Colombi, Sabrina Giordano
Publikováno v:
Statistica, Vol 66, Iss 1, Pp 19-38 (2013)
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 independencies introduced in order to describe if the knowledge of past or present realizatio
Externí odkaz:
https://doaj.org/article/4db7e9d73809439192fe677dc63985da
Publikováno v:
Journal of Educational and Behavioral Statistics. 46:682-716
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 the scale regardless of the content of the item (response styles) and purely content-driven
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::777a30bfab4b2afec594a0bd47fb724b
https://doi.org/10.3102/1076998621992554
https://doi.org/10.3102/1076998621992554
Publikováno v:
Statistical Methods & Applications. 28:441-444
We focus on on the multivariate extensions of CUB/GEM models. The interest of rating surveys is rarely focused on a single item or on a single aspect of an item. Respondents are often requested to express their opinion on different aspects of an issu
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::906683747e2c9074bfe6996b2f3a0948
https://doi.org/10.1007/s10260-019-00463-z
https://doi.org/10.1007/s10260-019-00463-z
Autor:
Roberto Colombi, Sabrina Giordano
Publikováno v:
TEST. 28:1175-1202
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 for uncertain answers (Colombi et al. in Scand J Stat, 2018. https://doi.org/10.1111/sjos.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::df3b69a36d079199c2141646c4fbea1b
https://doi.org/10.1007/s11749-019-00626-w
https://doi.org/10.1007/s11749-019-00626-w
Publikováno v:
Health Economics. 26:5-22
In this paper, we extend the 4-random-component closed skew-normal stochastic frontier model by including exogenous determinants of hospital persistent (long-run) and transient (short-run) inefficiency, separated from unobserved heterogeneity. We app
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::48b3531acd5e4a7103ca6d8024c2dfec
https://doi.org/10.1002/hec.3557
https://doi.org/10.1002/hec.3557
Autor:
Sabrina Giordano, Roberto Colombi
Publikováno v:
Biometrical journal. Biometrische ZeitschriftREFERENCES. 62(5)
In many fields, people are requested to express their level of awareness about some risk (mainly associated with health, environment, energy, etc.) by selecting a category in an ordered scale. We propose a model for such ordinal data by taking into a
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4ea37065c86406b8d657b3a62f0b1162
https://pubmed.ncbi.nlm.nih.gov/32077132
https://pubmed.ncbi.nlm.nih.gov/32077132
In responding to a rating question, an individual may give answers either according to his/her knowledge/awareness or to his/her level of indecision/uncertainty, typically driven by a response style. As ignoring this dual behavior may lead to mislead
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ee503edc57dc88052adff4c88a7ac5a6
http://hdl.handle.net/10446/131431
http://hdl.handle.net/10446/131431
Autor:
Antonio Forcina, Roberto Colombi
Publikováno v:
Statistical Methods & Applications. 25:501-517
This paper introduces some new models of ecological inference within the context of estimation of voter transitions across elections. In particular, we assume that voters of a given party in a given occasion may be split into two latent types: faithf
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::33702ea342f46e252a53a5154d289981
https://doi.org/10.1007/s10260-015-0349-0
https://doi.org/10.1007/s10260-015-0349-0
Autor:
Roberto Colombi, Sabrina Giordano
Publikováno v:
Journal of Multivariate Analysis. 140:19-30
We introduce multiple hidden Markov models (MHMMs) where an observed multivariate categorical time series depends on an unobservable multivariate Mar- kov chain. MHMMs provide an elegant framework for specifying various independence relationships bet
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ffc0eab16668352b2e8afd7485beff4f
https://doi.org/10.1016/j.jmva.2015.04.002
https://doi.org/10.1016/j.jmva.2015.04.002