Exchangeable models of heterogeneity, mixtures, and multivariate aging properties
نویسنده
چکیده
We compare multivariate aging notions of conditionally independent lifetimes with corresponding univariate aging notions of their one-dimensional marginal distributions. Let G(t|θ) (t ≥ 0) be a one-dimensional survival function indexed by θ; for simplicity’s sake, we assume here that θ is a non-negative scalar quantity; let, furthermore, Π be a probability distribution over [0,∞) and consider the (mixture-type) one-dimensional survival function defined by
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