Managing requirements uncertainty with partial models

Models are good at expressing information that is known but do not typically have support for representing what information a modeler does not know at a particular phase in the software development process. Partial models address this by being able to precisely represent uncertainty about model content. In previous work, we developed a general approach for defining partial models and applied it to capturing uncertainty, including reasoning over design models containing uncertainty. In this paper, we show how to apply our approach to managing requirements uncertainty. In particular, we address the problem of specifying uncertainty within a requirements model, refining a model as uncertainty reduces and reasoning with traceability relations between models containing uncertainty. We illustrate our approach using the meeting scheduler example.