Blending Descriptive and Numeric Analysis in Human Reliability Design

Scenario based design allows for the early elicitation of requirements and can be helpful in the design phase of system development. It is typical for cycles of iteration to be used to refine a design so that it more closely meets its requirements. Such refinements are in terms of the original requirements specification and any new requirements that have been identified. However, not all defined requirements are equally essential. Although descriptive methods for scenario analysis can be used to highlight new requirements, it can be difficult to evaluate the impact of these new requirements. In this paper, we exemplify this problem and investigate how numeric methods can be used to highlight the impact of consequences identified by descriptive scenario analysis. An example from the context of human reliability analysis is presented.