Supporting quantitative assessment of requirements in Goal Orientation

Goal-Orientation provides a rich framework for reasoning about systems during the Requirements Engineering (RE) phase. While critical properties like safety or security can require formal semantics, performing quantitative reasoning on semi-formal models in a much more lightweight approach reveals to be sufficient in many projects. Most of the time, existing RE tools only target specific quantification scenarios or do not provide easy mechanisms for implementing them. In order to demonstrate the ability to provide mechanisms that are both generic and powerful, we developed an extension of the Objectiver tool in three directions: (1) internal reasoning capabilities on AND-OR goal/obstacles structures, (2) close integration with an external spreadsheet application and (3) model export for building assessment tools using model-driven engineering techniques. We also demonstrate how our approach can cope with a variety of industrial scenarios requiring some form of quantification such as risk analysis, selection of design alternatives, effort estimation, and assessment of customer satisfaction.