Quantitative Analysis for Requirements Evolution's Ripple-Effect

One certainty in software development is that requirements always evolve. To effectively handle requirements evolution, determining the impact of requirements evolution from quantitative perspectives is a breakthrough. This paper first defines labelled requirements and requirements models by array, which is simple and effective to express requirements or models. Then respectively creates requirements model adjacency matrix and reachability matrix . Depending on matrix shift and calculation, a series of Requirements Evolution ripple-effects are formularized. At the same time, ripple-effect analysis for requirements evolution operations is discussed. An example supports the quantitative models underlying the proposed metrics. This work provides a new method for effectively managing and controlling and evaluating requirements evolution, and building an effect requirements analysis and management tool.