Modelo unibimodal simétrico-asimétrico con aplicación al estudio del RNA VIH-1

• Martínez Flórez, Guillermo ^[2] ; Moreno Arenas, Germán ^[1]
  1. [1] Universidad Industrial de Santander

     Universidad Industrial de Santander

     Colombia

     
  2. [2] Universidad de Córdoba
• Localización: Integración: Temas de matemáticas, ISSN 0120-419X, Vol. 32, Nº. 1, 2014 (Ejemplar dedicado a: Revista Integración), págs. 1-18
• Idioma: español
• Títulos paralelos:
  • Uni-bimodal Symmetric-Asymmetric Model with Application to the Study of HIV-1 RNA
• Enlaces
  • Texto completo (pdf)
• Resumen
  • español

    Se definen dos nuevas distribuciones de probabilidad: modelo unibimodal simétrico con función de riesgo proporcional a la distribución normal y modelo unibimodal asimétrico con función de riesgo proporcional a la distribución normal asimétrica. Estos modelos permiten ajustar datos censurados con comportamiento bimodal y altos (o bajos) niveles de curtosis comparado con la curtosis de la distribución normal y altos (o bajos) niveles de asimetría. Además, se estiman los parámetros de los modelos por máxima verosimilitud y se determina la matriz de información observada. La flexibilidad de la nueva distribución se ilustra ajustando un conjunto de datos reales: el número de moléculas de ARN VIH-1 por mililitros de sangre medida en personas con pruebas confirmadas de presencia del VIH. 

  • English

    We define two new probability distributions, unibimodal symmetric model with proportional hazard function to the normal distribution and unibimodal asymmetric model with proportional hazard function to the skew normal distribution. These models allow adjust censored data with bimodal behavior and high (or low) levels of kurtosis compared with kurtosis of the normal distribution and high (or low) levels of asymmetry. The model parameters are estimated by maximum likelihood and the observed information matrix is determined. The flexibility of the new distribution is illustrated by adjusting a set of real data, the number of molecules of HIV-1 RNA per milliliter of blood measured in individuals with confirmed test of the presence of HIV.

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