<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Donzé, Laurent</dc:contributor>
  <dc:creator>Berkachy, Rédina</dc:creator>
  <dc:date>2020</dc:date>
  <dc:description xmlns:ns0="xml" ns0:lang="en">This thesis intends to present some advances in fuzzy statistical analyses.  A particular distance between fuzzy numbers called the signed distance, seems to be appealing  because of its directional property. It has the ability of describing the direction of  travel between two fuzzy numbers. In addition, it has been often used as a fuzzy ranking tool  or a defuzzification operator. Despite the fact that this distance appears to have interesting  properties, it presents serious drawbacks. To overcome these problems, this thesis develops  improved versions of it given by two L2 metrics for which the first one is directional and  preserves the properties of the signed distance, and the other one is non-directional. Both  sophisticated distances have the advantage of taking into consideration the shapes of the fuzzy numbers  and their possible irregularities. The core aim of this thesis is therefore to apply these novel  distances in a serie of statistical approaches defined on the set of fuzzy numbers. Based on the  proposed distances, this thesis  provides a methodology of testing hypotheses in the fuzzy environment.  This method of testing relies on  the estimation of fuzzy confidence intervals, where we consider not only the  data as fuzzy, but also the  hypotheses. As such, the defended distances are used at different stages  of the process of the inference  test: in the conception of the models themselves or as defuzzification  operators of the obtained fuzzy  decisions. Moreover, since the traditional way of estimating fuzzy  confidence intervals is in some sense  limited in terms of the chosen parameters and the involved distributions,  this thesis presents a practical  procedure of estimation of such intervals based on the likelihood method.  This new procedure is seen as  general, since it can be used with any type of parameter and without the  obligation of a priori defining a  particular distribution. Analogously to this testing model, a definition of the  fuzzy p-value described in the  same setups with its corresponding decision rule is given. In this context, a  defuzzification of this fuzzy p- value can be of good use to get a crisp interpretable decision. Furthermore,  this thesis presents two  conceptually different applications in which the defended distances are  involved. On a first stage, a novel  methodology of assessment of linguistic questionnaires is developed on  two distinct levels: the global and  the individual ones. The proposed procedure has the great possibility of  being able to treat the sampling  weights and the eventual missingness occurring in the concerned data  sets. The second application  consists on an extension of the multi-ways analysis of variance to the  space of fuzzy sets. The decision  related to the corresponding test statistic can be made according to two  decision rules: a heuristic one  preserving the fuzzy nature of the sums of squares, and another crisp one  based on the defended  distances. To illustrate these approaches, multiple empirical and simulation  studies are displayed using  synthetic and real data sets. Note that a prominent objective of these  studies is to investigate empirically  some different statistical contexts, and theoretically the use of the newly  introduced distances compared to  known ones from one side, and to the results obtained from the  conventional statistical theory from another  one. A recurrent general finding is that the classical approach seems to be  a particular case of the fuzzy  one. As such, the mentioned fuzzy approaches seem to be potentionally  promising. A coherent R package  covering all the previously mentioned concepts with complete  documentation and some use cases are  finally described. This package is developed from scratch in compliance  with all the theoretical tools  presented in a user-friendly comprehensive programming environment with  a big panoply of calculation  methods.</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>https://folia.unifr.ch/global/documents/308986</dc:identifier>
  <dc:identifier>https://folia.unifr.ch/documents/308986/files/BerkachyR.pdf</dc:identifier>
  <dc:language>eng</dc:language>
  <dc:relation>info:eu-repo/semantics/altIdentifier/urn/urn:nbn:ch:rero-002-121410</dc:relation>
  <dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
  <dc:rights>License undefined</dc:rights>
  <dc:subject>info:eu-repo/classification/udc/6</dc:subject>
  <dc:title xmlns:ns1="xml" ns1:lang="en">The signed distance measure in fuzzy statistical analysis : Some theoretical, empirical and programming advances</dc:title>
  <dc:type>http://purl.org/coar/resource_type/c_db06</dc:type>
</oai_dc:dc>
