Basic Reliability Functions
Problem of aging affects many of systems and their components. This phenomenon have been widely studied in the field of reliability theory. Properties of random lifetimes are usually described by means of their respective distribution, survival and failure rate (hazard rate) functions. The aging intensity function is a relatively new concept that can be also used in lifetime analysis. In Sect. 1.1 this function is defined for nonnegative univariate absolutely continuous distributions. Further one, we extend the notion of aging intensity for the case of univariate discrete distributions (Sect. 1.2), bivariate absolutely continuous distributions (Sect. 1.3) and bivariate discrete distributions (Sect. 1.4).