Automating analysis of qualitative preferences in goal-oriented requirements engineering

In goal-oriented requirements engineering, a goal model graphically represents relationships between the required goals (functional requirements), tasks (realizations of goals), and optional goals (non-functional properties) involved in designing a system. It may, however, be impossible to find a design that fulfills all required goals and all optional goals. In such cases, it is useful to find designs that provide the required functionality while satisfying the most preferred set of optional goals under the goal model's constraints. We present an approach that considers expressive qualitative preferences over optional goals, as these can model interacting and/or mutually exclusive subgoals. Our framework employs a model checking-based method for reasoning with qualitative preferences to identify the most preferred alternative(s). We evaluate our approach using existing goal models from the literature.