A Semi-Automated Tool for Requirements Trade-off Analysis

In designing most systems, requirements analysts face many competing requirements, such as performance, usability, costs, and so forth. Ideally, analysts would like to quantitatively measure consequences of solutions on requirements and risks, and extract stakeholders’ preferences in terms of numerical weights. However, during the early stages of requirements and system design, it is hard to quantitatively measure all factors on a similar scale and quantify stakeholders’ preferences. This contribution proposes a semi-automated decision aid tool which allows the use of available but potentially incomplete quantitative and qualitative requirements and risk measures. It removed the need to elicit importance weights of requirements. Instead, stakeholders are asked how much they would relax the demand on one objective to better achieve another. The proposed tool extends the Even Swap method with formally defined rules for suggesting the next swap to decision stakeholders.