Annals of Operations Research

, Volume 181, Issue 1, pp 515–538 | Cite as

Proposal of a new distribution in PERT methodology

  • Catalina Beatriz García García
  • José García Pérez
  • Salvador Cruz Rambaud


The aim of this paper is to present the generalized biparabolic distribution (GBP) as a good candidate to be utilized as the distribution underlying to PERT methodology (Malcolm et al. in Oper. Res. 7:646–669, 1959). To do this and following the criteria established by Taha (Investigación de Operaciones, 1981) and Herrerías (Estudios de Economía Aplicada, pp. 89–112, 1989), we will compare the mean and variance estimates derived from each proposed density function, viz beta, two-sided power (TSP) and GBP distributions. Also we will compare the estimates contributed by the mesokurtic and of constant variance families of the aforementioned distributions. The main conclusion is that the GBP distribution is the most convenient to be used in the PERT methodology because its mean is almost as moderate as that of trapezoidal and its variance is much higher than that of the rest of distributions. As a consequence, it can be stated that the GBP distribution is an alternative to the other four-parameter distributions.


Biparabolic TSP distribution PERT Constant variance Mesokurtic 


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Catalina Beatriz García García
    • 1
  • José García Pérez
    • 2
  • Salvador Cruz Rambaud
    • 3
  1. 1.Departamento de Métodos Cuantitativos para la Economía y la EmpresaUniversidad de GranadaGranadaSpain
  2. 2.Departamento de Economía AplicadaUniversidad de AlmeríaAlmeríaSpain
  3. 3.Departamento de Dirección y Gestión de EmpresasUniversidad de AlmeríaAlmeríaSpain

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