Relations among univariate aging, bivariate aging and dependence for exchangeable lifetimes (Q1776873)

For bivariate exchangeable distribution functions, the authors analyze the relations among some notions of bivariate aging, of univariate aging (of the common marginals), and of bivariate dependence. A natural tool for the analysis is the notion of semicopula. As examples, the authors characterize the Schur-concavity of the corresponding bivariate exchangeable survival function, and the IFR property of the (common) marginals. Archimedean survival copulae are studied in some detail.