Publicado 2014-05-22
Palabras clave
- Bimodalidad,
- asimetría,
- curtosis,
- función de riesgo proporcional,
- censura
- límite de detección,
- ARN VIH-1,
- HAART. ...Más
Cómo citar
Resumen
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.
Para citar este artículo: G. Martínez-Flórez, G. Moreno-Arenas, Modelo unibimodal simétrico-asimétrico con aplicación al estudio del RNA VIH-1, Rev. Integr. Temas Mat. 32 (2014), no. 1, 1–18.
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