  In this paper authors present a general methodology for age dependent
reliability analysis of degrading or ageing systems, structures and
components.The methodology is based on Bayesian methods and inference, its
ability to incorporate prior information and on idea that ageing can be thought
as age dependent change of believes about reliability parameters, when change
of belief occurs not just due to new failure data or other information which
becomes available in time, but also it continuously changes due to flow of time
and beliefs evolution. The main objective of this paper is to present the clear
way of how Bayesian methods can be applied by practitioners to deal with risk
and reliability analysis considering ageing phenomena. The methodology
describes step by step failure rate analysis of ageing systems: from the
Bayesian model building to its verification and generalization with Bayesian
model averaging which, as authors suggest in this paper, could serve as
alternative for various goodness of fit assessment tools and as universal tool
to cope with various sources of uncertainty.
