Generic parameterization of lifetime distributions

In statistics and in reliability it is conventional to define a set of parameters for each cumulative distribution function. In contrast, here the use of generic parameters is considered. In particular, the standard deviation of the natural logarithm of the lifetime and the median of the lifetime are shown to be attractive generic parameters for semiconductor-device lifetimes. These two generic parameters are then evaluated for Weibull, exponential, lognormal, and nonparametric representations of the lifetime distribution