Brazilian Journal of Probability and Statistics

The polysurvival model with long-term survivors

Josmar Mazucheli, Francisco Louzada, and Jorge A. Achcar

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Long-term survival models have historically been considered for analyzing time-to-event data with long-term survivors fraction. However, situations in which a fraction (1 − p) of systems is subject to failure from independent competing causes of failure, while the remaining proportion p is cured or has not presented the event of interest during the time period of the study, have not been fully considered in the literature. In order to accommodate such situations, we present in this paper a new long-term survival model. Maximum likelihood estimation procedure is discussed as well as interval estimation and hypothesis tests. A real dataset illustrates the methodology.

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Braz. J. Probab. Stat., Volume 26, Number 3 (2012), 313-324.

First available in Project Euclid: 5 April 2012

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Bootstrap maximum likelihood long-term survivors hypothesis tests survival analysis


Mazucheli, Josmar; Louzada, Francisco; Achcar, Jorge A. The polysurvival model with long-term survivors. Braz. J. Probab. Stat. 26 (2012), no. 3, 313--324. doi:10.1214/11-BJPS138.

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