Ara es mostren els items 26-45 de 53

    • Microbiome datasets are compositional: and this is not optional 

      Gloor, Gregory B.; Macklaim, Jean M.; Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José (2017-11)
      Article
      Accés obert
      Datasets collected by high-throughput sequencing (HTS) of 16S rRNA gene amplimers, metagenomes or metatranscriptomes are commonplace and being used to study human disease states, ecological differences between sites, and ...
    • Modelización de la peligrosidad sísmica: aplicación a Cataluña 

      Canas Torres, José Antonio; Egozcue Rubí, Juan José; Miquel Canet, Juan; Barbat Barbat, Horia Alejandro (Centre Internacional de Mètodes Numèrics en Enginyeria (CIMNE), 1996)
      Llibre
      Accés obert
      Un método Bayesiano para la evaluación de la probabilidad de ocurrencia de sismos. Pseudo-aceleraciones del terreno en el subbloque ibero-costero pirenaico. Determinación de las acciones sísmicas de diseño.
    • Modelling compositional change with simplicial linear ordinary differential equations 

      Jarauta Bragulat, Eusebio; Egozcue Rubí, Juan José (2013)
      Text en actes de congrés
      Accés obert
    • Modified Kolmogorov-Smirnov test of goodness of fit 

      Monti, Gianna S.; Mateu Figueras, Gloria; Ortego Martínez, María Isabel; Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José (2017)
      Text en actes de congrés
      Accés obert
      A modified version of the Kolmogorov-Smirnov (KS) test is presented as a tool to assess whether a specified, although arbitrary, probability model is unsuitable to describe the underlying distribution of a set of observations. ...
    • Power bias in maximum entropy spectral analysis 

      Egozcue Rubí, Juan José; Pagès Fita, Jaume (Universitat Politècnica de Barcelona. Centre de Càlcul, 1983-06)
      Article
      Accés obert
      Several algorithms have been used in maximum entropy spectral analysis. Among them, the standard Burg procedure and the forward-backward least squares method are considered. When the autoregressive model, which is implicit ...
    • Principal balances 

      Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José; Tolosana Delgado, Raimon (International Centre for Numerical Methods in Engineering (CIMNE), 2011)
      Text en actes de congrés
      Accés obert
      Principal balances are defined as a sequence of orthonormal balances which maximize successively the explained variance in a data set. Apparently, computing principal balances requires an exhaustive search along all possible ...
    • Principal balances 

      Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José; Tolosana Delgado, Raimon (CIMNE, 2011)
      Text en actes de congrés
      Accés obert
      Principal balances are de ned as a sequence of orthonormal balances which maximize successively the explained variance in a data set. Apparently, computing principal balances requires an exhaustive search along all ...
    • Probabilistic analysis of an a posteriori error estimator for finite elements 

      Díez, Pedro; Egozcue Rubí, Juan José (2001-08)
      Article
      Accés obert
      A residual type a posteriori error estimator for finite elements is analyzed using a new technique. In this case, the error estimate is the result of two consecutive projections of the exact error on two finite-dimensional ...
    • Proportionality: a valid alternative to correlation for relative data 

      Lovell, David; Pawlowsky-Glahn, Vera; Egozcue Rubí, Juan José; Marguerat, Samuel; Baehler, Juerg (2015-03-01)
      Article
      Accés obert
      In the life sciences, many measurement methods yield only the relative abundances of different components in a sample. With such relative-or compositional-data, differential expression needs careful interpretation, and ...
    • Relationship between popularity of key words in the Google browser and the evolution of worldwide financial indexes 

      ORTELLS SESÉ, ROBERT; Egozcue Rubí, Juan José; Ortego Martínez, María Isabel; Garola Crespo, Àlvar (2015)
      Text en actes de congrés
      Accés obert
      The purpose of this contribution is to evaluate whether there is enough statistical basis to establish a relationship between the popularity of certain terms in the Google, Inc. browser and the evolution of several worldwide ...
    • Relationship between the popularity of key words in the Google browser and the evolution of worldwide financial indices 

      Ortells Sesé, Robert; Egozcue Rubí, Juan José; Ortego Martínez, María Isabel; Garola Crespo, Àlvar (Springer, 2016)
      Capítol de llibre
      Accés restringit per política de l'editorial
      The authoritative contributions gathered in this volume reflect the state of the art in compositional data analysis (CoDa). The respective chapters cover all aspects of CoDa, ranging from mathematical theory, statistical ...
    • Reply to 

      Egozcue Rubí, Juan José (2009-10)
      Article
      Accés restringit per política de l'editorial
    • Rethinking the Kolmogorov-Smirnov test of Goodness of fit in a compositional way 

      Monti, Gianna S.; Mateu Figueras, Gloria; Ortego Martínez, María Isabel; Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José (Pearson, 2018)
      Text en actes de congrés
      Accés obert
      The Kolmogorov Smirnov test (KS) is a well known test used to asses how a set of observations is significantly different from the probability model specified under the null hypothesis. The KS test statistic quantifies the ...
    • Some thoughts on counts in sequencing studies 

      Egozcue Rubí, Juan José; Graffelman, Jan; Ortego Martínez, María Isabel; Pawlowsky Glahn, Vera (2020-12-01)
      Article
      Accés obert
      Measurements in sequencing studies are mostly based on counts. There is a lack of theoretical developments for the analysis and modelling of this type of data. Some thoughts in this direction are presented, which might ...
    • Space-time compositional models: an introduction to simplicial partial differential operators 

      Jarauta Bragulat, Eusebio; Egozcue Rubí, Juan José (2015)
      Text en actes de congrés
      Accés obert
      A function assigning a composition to space-time points is called a compositional or simplicial field. These fields can be analysed using the compositional analysis tools. A study of linear models for evolutionary compositions ...
    • Spatial analysis of compositional data : a historical review 

      Pawlowsky-Glahn, Vera; Egozcue Rubí, Juan José (2016-05-01)
      Article
      Accés obert
      Like the statistical analysis of compositional data in general, spatial analysis of compositional data requires specific tools. A historical overview of their development is presented in three steps: (a) the recognition ...
    • Spectral analysis of the Beznar dam accelerogram. Comparison with results in the northeastern of Spain 

      Canas Torres, José Antonio; Barbat Barbat, Horia Alejandro; Pujades Beneit, Lluís; Egozcue Rubí, Juan José; Sarrate Ramos, Josep (1991-12)
      Article
      Accés obert
      Numerical analysis applied to the Beznar dam accelerograms (longitudinal and transversal components) shows that the Fourier amplitude spectrum is a good approximation to the pseudo-velocity spectra. Thís fact makes possible ...
    • Spurious copulas 

      Ortego Martínez, María Isabel; Egozcue Rubí, Juan José (2013)
      Text en actes de congrés
      Accés obert
      Modeling dependence between two or more variables is a common issue in statistical applications. The Pearson correlation coefficient is often used to measure dependence, although it
    • Structure and metabolic potential of the prokaryotic communities from the hydrothermal system of Paleochori Bay, Milos, Greece 

      Le Moine Bauer, Sven; Lu, Guang-Sin; Goulaouic, Steven; Puzenat, Valentine; Schouw, Anders; Barreyre, Thibaut; Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José; Martelat, Jean Emmanuel; Escartin, Javier; Amend, Jan; Nomikou, Paraskevi; Vlasopoulos, Othonas; Polymenakou, Paraskevi; Jørgensen, Steffen Leth (Frontiers Media SA, 2023-01-06)
      Article
      Accés obert
      Introduction: Shallow hydrothermal systems share many characteristics with their deep-sea counterparts, but their accessibility facilitates their study. One of the most studied shallow hydrothermal vent fields lies at ...
    • Survey data on perceptions of contraceptive methods as compositional tables 

      Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José; Planes Pedra, Montserrat (2018-07)
      Article
      Accés obert
      This paper studies the relative evaluation of young people and the possible benefits associated with three methods of avoiding sexually transmitted infections/AIDS and/or unwanted pregnancies (condoms, contraceptive pills, ...