Browsing by Author "Egozcue Rubí, Juan José"Més informacióMés informació

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    • 40 years after Aitchison’s article “The statistical analysis of compositional data”. Where we are and where we are heading 

      Coenders, Germà; Egozcue Rubí, Juan José; Facevicova, Kamila; Navarro López, Carolina; Palarea Albadalejo, Javier; Pawlowsky Glahn, Vera; Tolosana Delgado, Raimon (2023)
      Article
      Open Access
      The year 2022 marked 40 years since Aitchison published the article “The statistical analysis of compositional data”. It is considered to be the foundation of contemporary compositional data analysis. It is time to review ...

    • A posteriori error estimation for standard finite element analysis 

      Díez, Pedro; Egozcue Rubí, Juan José; Huerta, Antonio (1998-09)
      Article
      Open Access
      A new residual type estimator based on projections of the error on subspaces of locally-supported functions is presented. The estimator is defined by a standard element-by-element refinement. First, an approximation of the ...

    • Air quality index revisited from a compositional point of view 

      Jarauta Bragulat, Eusebio; Hervada Sala, Carme; Egozcue Rubí, Juan José (2016-06)
      Article
      Open Access
      The so-called Air Quality Index (AQI), expresses the quality of atmospheric air. The overall AQI is determined from the AQIs of some reference air pollutants, which are calculated by a transform of the respective concentrations. ...

    • Análisis de datos composicionales: aguas, contaminantes, recursos, sociología... 

      Egozcue Rubí, Juan José; Tolosana Delgado, Raimon; Jarauta Bragulat, Eusebio; Ortego Martínez, María Isabel; Díaz Barrero, José Luis (Universitat Politècnica de Catalunya. Escola Tècnica Superior d'Enginyers de Camins Canals i Ports de Barcelona, 2011-11-15)
      Conference lecture
      Open Access
      Los datos composicionales describen las partes de un todo. Se presentan en forma de vectores proporciones, porcentajes, concentraciones químicas etc. y aparecen en multitud de campos de la ciencia y la ingeniería. A pesar ...

    • Análisis y previsión de fenómenos naturales peligrosos 

      Tolosana Delgado, Raimon; Egozcue Rubí, Juan José; Ortego Martínez, María Isabel; Sánchez-Arcilla Conejo, Agustín (Universitat Politècnica de Catalunya. Escola Tècnica Superior d'Enginyers de Camins Canals i Ports de Barcelona, 2011-11-16)
      Conference lecture
      Open Access
      La toma de decisiones referentes al diseño o en sistemas de alerta requieren el estudio de las acciones externas (frecuentemente meteorológicas), la descripción probabilista del sistema (vulnerabilidad, susceptibilidad) ...

    • Approaching predator-prey Lotka-Volterra equations by simplicial linear differential equations 

      Jarauta Bragulat, Eusebio; Egozcue Rubí, Juan José (CIMNE, 2011)
      Conference report
      Open Access
      Predator-prey Lotka-Volterra equations was one of the rst models reflecting interaction of different species and modeling evolution of respective populations. It considers a large population of hares (preys) which is ...

    • Balances: a new perspective for microbiome analysis 

      Rivera Pinto, J.; Egozcue Rubí, Juan José; Pawlowsky Glahn, Vera; Paredes, Raul; Noguera Julian, Marc; Calle, M. L. (2018-07)
      Article
      Open Access
      High-throughput sequencing technologies have revolutionized microbiome research by allowing the relative quantification of microbiome composition and function in different environments. In this work we focus on the ...

    • Bayes linear spaces 

      van den Boogaart, Karl Gerald; Egozcue Rubí, Juan José; Pawlowsky Glahn, Vera (Institut d'Estadística de Catalunya, 2010)
      Article
      Open Access
      Linear spaces consisting of -finite probability measures and infinite measures (improper priors and likelihood functions) are defined. The commutative group operation, called perturbation, is the updating given by Bayes ...

    • Bayes linear spaces 

      van den Boogaart, Karl Gerald; Egozcue Rubí, Juan José; Pawlowsky Glahn, Vera (2010-12)
      Article
      Open Access
      Linear spaces consisting of $\sigma$-finite probability measures and infinite measures (improper priors and likelihood functions) are defined. The commutative group operation, called perturbation, is the updating given by ...

    • Bayesian estimation of the orthogonal decomposition of a contingency table 

      Ortego Martínez, María Isabel; Egozcue Rubí, Juan José (2015)
      Conference report
      Open Access
      Contingency tables can be parametrized by probabilities of each cell in a multinomial sampling. These probabilities constitute the joint probability function of the two or more discrete random categorical variables. These ...

    • Bayesian estimation of the orthogonal decomposition of a contingency table 

      Ortego Martínez, María Isabel; Egozcue Rubí, Juan José (2016)
      Article
      Open Access
      In a multinomial sampling, contingency tables can be parametrized by probabilities of each cell. These probabilities constitute the joint probability function of two or more discrete random variables. These probability ...

    • Bayesian trend analysis for daily rainfall series of Barcelona 

      Ortego Martínez, María Isabel; Gibergans Bàguena, José; Tolosana Delgado, Raimon; Egozcue Rubí, Juan José; Llasat Botija, Maria Carmen (2010-07-15)
      Article
      Open Access
      A Point-Over-Threshold approach using a reparameterization of the Generalized Pareto Distribution (GPD) has been used to assess changes in the daily rainfall Barcelona series (1854–2006). A Bayesian approach, considering ...

    • Checking model-data weather hazard occurrence fit in the context of climate change 

      Tolosana Delgado, Raimon; Ortego Martínez, María Isabel; Egozcue Rubí, Juan José; Sánchez-Arcilla Conejo, Agustín (2011)
      Conference report
      Open Access
      In climate change impact studies it is common to run a given response model (from ecosystem changes to wavestorm or landslide occurrence) nested into one of the available long-term Global or Regional Circulation Models ...

    • Chronic kidney disease of unknown origin is associated with environmental urbanisation in Belfast, UK 

      McKinley, Jennifer M.; Mueller, Ute; Atkinson, Peter M.; Ofterdinger, Ulrich; Cox, Siobhan F.; Doherty, Rory; Fogarty, Damian; Egozcue Rubí, Juan José; Pawlowsky Glahn, Vera (2021-07)
      Article
      Open Access
      Chronic kidney disease (CKD), a collective term for many causes of progressive renal failure, is increasing worldwide due to ageing, obesity and diabetes. However, these factors cannot explain the many environmental clusters ...

    • Classifying wave forecasts with model-based geostatistics and the Aitchison distribution 

      Tolosana Delgado, Raimon; Egozcue Rubí, Juan José; Sánchez-Arcilla Conejo, Agustín; Gómez Aguar, Jesús Javier (2010)
      Conference report
      Restricted access - publisher's policy

    • Climate change in a Point-Over-Threshold model: an example on ocean-wave-storm hazard in NE Spain 

      Tolosana Delgado, Raimon; Ortego Martínez, María Isabel; Egozcue Rubí, Juan José; Sánchez-Arcilla Conejo, Agustín (2010-09-27)
      Article
      Open Access
      A reparametrization of the Generalized Pareto Distribution is here proposed. It is suitable to parsimoniously check trend assumptions within a Point-Over-Threshold model of hazardous events. This is based on considerations ...

    • Compositional data techniques for the analysis of the container traffic share in a multi-port region 

      Grifoll Colls, Manel; Ortego Martínez, María Isabel; Egozcue Rubí, Juan José (Springer, 2019-12)
      Article
      Open Access
      The statistical techniques based on compositional data are applied to investigate the evolution of the traffic share of the container throughput in a multi-port system. Compositional vectors are those which contain relative ...

    • Descripción del oleaje por el método de las direcciones instantáneas 

      Arribas Perea, Miguel Ángel; Egozcue Rubí, Juan José (1992-12)
      Article
      Open Access
      Se presenta el método de las direcciones instantáneas para la descripción del oleaje. El punto de partida es el hecho de que las series temporales de la elevación de la superficie del mar contienen más información que la ...

    • Estimació del pol i de la variància del soroll d'un model AR(1) mitjançant filtratge no lineal 

      Muñoz Gracia, María del Pilar; Martí Recober, Manuel; Egozcue Rubí, Juan José (Universitat Politècnica de Barcelona. Centre de Càlcul, 1988)
      Article
      Open Access
      L'estimació dels paràmetres associats a un procés ARMA es pot plantejar com un problema de filtratge no lineai. Per determinar un estimador recursiu d'aquests paràmetres es deflneix un vector d'estat ampliat que inclou les ...

    • Estimación del parámetro b de Richter a partir de las medidas imprecisas de intensidad epicentral 

      Forcada Plaza, Santiago; Egozcue Rubí, Juan José (Institut d'estadística de Catalunya, 1996)
      Article
      Open Access
      El objetivo de este trabajo es la estimación del parámetro exponencial de Richter que determina la distribución de probabilidad de la variable intensidad de movimientos sísmicos que se producen en una determinada zona. Las ...