Now showing items 21-33 of 33

    • 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)
      Conference report
      Open Access
      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. ...
    • Multivariate hybrid modelling of future wave-storms at the northwestern Black Sea 

      Lin Ye, Jue; García León, Manuel; Gracia Garcia, Vicente; Ortego Martínez, María Isabel; Stanica, Adrian; Sánchez-Arcilla Conejo, Agustín (2018-02)
      Article
      Open Access
      The characterization of future wave-storms and their relationship to large-scale climate can provide useful information for environmental or urban planning at coastal areas. A hybrid methodology (process-based and statistical) ...
    • Multivariate statistical modelling of future marine storms 

      Lin Ye, Jue; García León, Manuel; Gracia Garcia, Vicente; Ortego Martínez, María Isabel; Lionello, Piero; Sánchez-Arcilla Conejo, Agustín (2017-04)
      Article
      Open Access
      Extreme events, such as wave-storms, need to be characterized for coastal infrastructure design purposes. Such description should contain information on both the univariate behaviour and the joint-dependence of storm-variables. ...
    • Pluviometric regionalization of Catalunya: a compositional data methodology 

      Gibergans Bàguena, José; Ortego Martínez, María Isabel; Tolosana Delgado, Raimon (Centro Internacional de Métodos Numéricos en Ingeniería (CIMNE), 2011)
      Conference report
      Open Access
      The aim of this paper is to introduce a methodology for de¯ning groups from regionalized com- positional data, through a hierarchical clustering algorithm aware of both the spatial dependence and the compositional character ...
    • 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)
      Conference report
      Open Access
      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)
      Part of book or chapter of book
      Restricted access - publisher's policy
      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 ...
    • 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)
      Conference report
      Open Access
      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
      Open Access
      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 ...
    • Spurious copulas 

      Ortego Martínez, María Isabel; Egozcue Rubí, Juan José (2013)
      Conference report
      Open Access
      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
    • Tree ecosystem services, for everyone? A compositional analysis approach to assess the distribution of urban trees as an indicator of environmental justice 

      Cruz Sandoval, Marco Antonio; Ortego Martínez, María Isabel; Roca Bosch, Elisabet (2020-02-07)
      Article
      Open Access
      Trees provide a broad amount of ecosystem services in urban areas. Although it is well documented that trees are essential for the well-being and livability of cities, trees are often not evenly distributed. Studies have ...
    • 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 (2009-09-11)
      Conference report
      Open Access
      Frequency analysis of hydrological series is a key point to acquire an in-depth understanding of the behaviour of hydrologic events. The occurrence of extreme hydrologic events in an area may imply great social and ...
    • Use of statistical tools in a development context analysis of variance (ANOVA) 

      Ortego Martínez, María Isabel; Lloret, Enric (GDEE, 2015)
      Part of book or chapter of book
      Open Access
    • Wind/Wave directional modelling: a compositional approach 

      Ortego Martínez, María Isabel; Egozcue Rubí, Juan José; Gómez Aguar, Jesús Javier; Mösso Aranda, César; Sánchez-Arcilla Conejo, Agustín (2015)
      Conference lecture
      Open Access