Valença, Dione MariaFonseca, Renata Santana2014-12-172009-06-102014-12-172009-03-06FONSECA, Renata Santana. Modelos de sobrevivência com fração de cura e omissão nas covariáveis. 2009. 74 f. Dissertação (Mestrado em Probabilidade e Estatística; Modelagem Matemática) - Universidade Federal do Rio Grande do Norte, Natal, 2009.https://repositorio.ufrn.br/jspui/handle/123456789/17004In this work we study the survival cure rate model proposed by Yakovlev (1993) that are considered in a competing risk setting. Covariates are introduced for modeling the cure rate and we allow some covariates to have missing values. We consider only the cases by which the missing covariates are categorical and implement the EM algorithm via the method of weights for maximum likelihood estimation. We present a Monte Carlo simulation experiment to compare the properties of the estimators based on this method with those estimators under the complete case scenario. We also evaluate, in this experiment, the impact in the parameter estimates when we increase the proportion of immune and censored individuals among the not immune one. We demonstrate the proposed methodology with a real data set involving the time until the graduation for the undergraduate course of Statistics of the Universidade Federal do Rio Grande do Norteapplication/pdfAcesso AbertoAnálise de sobrevivênciaFração de curaVariáveis omissasAlgoritmo EMSurvival analysisRate cureMissing dataEM algorithmmasterThesisCNPQ::CIENCIAS EXATAS E DA TERRA::MATEMATICA::MATEMATICA APLICADA