Abstract
In a population of individuals, where the random variable (r.v.) σ denotes the birth time and X the lifetime, we consider the case, where an individual can be observed only if its life-line \(\mathcal{L}\)(σ, X) = {(σ + y, y), 0 ≤ y ≤ X} intersects a given Borel set S in ℝ × ℝ+. Denoting by σ S and X S the birth time and lifetime for the observed individuals, we point out that the distribution function (d.f.) F S of the r.v. X S suffers from a selection bias in the sense that F S = ∝ w d F/μ S, where w and μ S depend only on the distribution of σ and on F, the d.f. of X. Assuming in addition that the r.v. X S is randomly right-censored as soon as the individual is selected, we construct a productlimit estimator \(\hat F_\mathcal{S} \) for the d.f. F S and a nonparametric estimator ŵ for the weight function w. We prove a consistency result for ŵ and a weak convergence result for \(\hat F_\mathcal{S} \). We establish in addition an exponential bound for \(\hat F_\mathcal{S} \).
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Guilloux, A. Nonparametric estimation for censored lifetimes suffering from unknown selection bias. Math. Meth. Stat. 16, 202–216 (2007). https://doi.org/10.3103/S1066530707030027
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DOI: https://doi.org/10.3103/S1066530707030027
Key words
- counting process
- exponential bound
- nonparametric inference
- martingale
- right-censored data
- selection-bias
- weak convergence of processes