Context transformations for goal models

This paper proposes a technique to support the requirements engineer in transforming existing models into new models to address the customer's needs. In particular, we identify a set of possible categories of context change that indicate in which direction the original model needs to evolve. Furthermore, we associate a transformation to each category, and we formalise it in terms of graph grammars. Our results are a generalisation of an experimental evaluation based on 10 models retrieved from the literature and 25 scenarios of context change. This work represents a step forward in the formalisation of requirements models since it provides the foundations of a tool to support the automatic transformation of models, and employs graph grammars to provide a formal layer to the approach.