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Computational Statistics

, Volume 22, Issue 3, pp 411–427 | Cite as

A functional analysis of NOx levels: location and scale estimation and outlier detection

  • Manuel Febrero
  • Pedro Galeano
  • Wenceslao González-ManteigaEmail author
Original Paper

Abstract

This paper analyzes the NOx levels measured by a control station near a power plant by using techniques for functional data. First, we test for differences between the levels on working and non working days. Second, we obtain several location estimators and confidence sets of the center of the functional distribution. Third, we provide scale estimators and confidence sets of the dispersion of the functional distribution. Finally, a distance based procedure provides a criterion to determinate the presence of outlying observations, which allows to detect relevant NOx levels.

Keywords

Functional data analysis Functional mode Functional trimmed means Functional trimmed standard deviation NOx levels Outliers 

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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Manuel Febrero
    • 1
  • Pedro Galeano
    • 1
  • Wenceslao González-Manteiga
    • 1
    Email author
  1. 1.Departamento de Estadística e Investigación OperativaUniversidad de Santiago de CompostelaSantiago de CompostelaSpain

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