Log-ratio methods in mixture models for compositional data sets

When traditional methods are applied to compositional data misleading and incoherent results could be obtained. Finite mixtures of multivariate distributions are becoming increasingly important nowadays. In this paper, traditional strategies to fit a mixture model into compositional data sets are re...

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Detalles Bibliográficos
Autores: Comas Cufí, Marc, Martín-Fernández, Josep Antoni, Mateu-Figueras, Glòria
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/112749
Acceso en línea:https://hdl.handle.net/2117/112749
Access Level:acceso abierto
Palabra clave:Compositional data
Finite Mixture
Log ratio
Model-based clustering
Normal distribution
Orthonormal coordinates
Simplex
Classificació AMS::62 Statistics::62E Distribution theory
Classificació AMS::62 Statistics::62G Nonparametric inference
Classificació AMS::62 Statistics::62H Multivariate analysis
Àrees temàtiques de la UPC::Matemàtiques i estadística::Estadística matemàtica
Descripción
Sumario:When traditional methods are applied to compositional data misleading and incoherent results could be obtained. Finite mixtures of multivariate distributions are becoming increasingly important nowadays. In this paper, traditional strategies to fit a mixture model into compositional data sets are revisited and the major difficulties are detailed. A new proposal using a mixture of distributions defined on orthonormal log-ratio coordinates is introduced. A real data set analysis is presented to illustrate and compare the different methodologies.