title: Piecewise exponential survival curves with smooth transitions.
abstract: Several models of a population survival curve composed of two piecewise exponential distributions are developed. In one formulation the hazard rate changes at a point that is an unobservable random variable that varies between individuals. The population hazard function may decrease with age even when all individuals' hazards are increasing. In a second formulation, the population hazard function is modeled directly. Several models are fit to the survival history of a cohort of 5751 highly inbred male Drosophila melanogaster and the British coal mining disaster data.
authors.affiliation: University of Minnesota, Minneapolis 55455.
authors.forename: D
authors.initials: D
authors.lastname: Zelterman
authors.forename: P M
authors.initials: PM
authors.lastname: Grambsch
authors.forename: C T
authors.initials: CT
authors.lastname: Le
authors.forename: J Z
authors.initials: JZ
authors.lastname: Ma
authors.forename: J W
authors.initials: JW
authors.lastname: Curtsinger
mesh_terms: D000818:Animals; D003032:Coal Mining; D004331:Drosophila melanogaster; D006801:Humans; D008297:Male; D008433:Mathematics; D008954:Models, Biological; D016016:Proportional Hazards Models; D016019:Survival Analysis; D006113:United Kingdom