A Simple Graphical Way of Evaluating Coverage and Directional Non-coverages

  • Adelaide FreitasEmail author
  • Sara Escudeiro
  • Vera Afreixo
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10405)


Evaluation of the coverage probability and, more recently, of the intervalar location of confidence intervals, is a useful procedure if exact and asymptotic methods for constructing confidence intervals are used for some populacional parameter. In this paper, a simple graphical procedure is presented to execute this kind of evaluation in confidence methods for linear combinations of k independent binomial proportions. Our proposal is based on the representation of the mesial and distal non-coverage probabilities on a plane. We carry out a simulation study to show how this graphical representation can be interpreted and used as a basis for the evaluation of intervalar location of confidence interval methods.


Coverage probability Mesial and distal non-coverage probabilities 



This work was partially supported by Portuguese funds through the CIDMA - Center for Research and Development in Mathematics and Applications, and the Portuguese Foundation for Science and Technology (FCT – Fundação para a Ciência e a Tecnologia), within project UID/MAT/04106/2013.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Adelaide Freitas
    • 1
    Email author
  • Sara Escudeiro
    • 2
  • Vera Afreixo
    • 1
  1. 1.University of AveiroAveiroPortugal
  2. 2.Polytechnic of Coimbra (ESAC)CoimbraPortugal

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