%J Mathware & Soft Computing
%D 2008
%V 15
%L eprints705
%N 1
%A Rachele Foschi
%A Fabio Spizzichino
%X We consider a pair of exchangeable lifetimes X, Y and the families of the conditional survival functions F t (x, y) of
(X ? t, Y ? t) given (X > t, Y > t). We analyze some properties of dependence and of ageing for F t (x, y) and
some relations among them
%I 	Seccio de Matematiques i Informatica, E.T.S. d'Arquitectura, Universitat Politecnica
%P 95-111
%T Semigroups of Semi-copulas and Evolution of Dependence at Increase of Age