Q. Applicability with reference to software reliability models?

Applicability: It is another important characteristic of a model. The model must be judged by its degree of applicability across software products that vary in size, structure and function. The model must be usable in different development environments different operational environments and different life cycle phases. It is enviable that a model should be robust with respect to deviations from its assumptions errors in the data or parameters it employs and unusual conditions.