Discrete Frailty
نویسنده
چکیده
In the standard frailty model the hazard function i s taken to be proportional to an unobserved random effect, specific to the individual. These frailties are the n taken to be independent realisations from a proba bility distribution of assumed form, and they are integrat ed out to form the likelihood function for the obse rved failure time data. In real applications the assumed istrib ution for frailty tends to be taken as continuous. However, there are situations in which a discrete frailty va riable is more appropriate. In this paper we presen t a framework for discrete frailty and evelop a score test for t he presence of frailty.
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A Summary of the Biological Basis of Frailty.
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