The Detection and Classification of Non-Functional Requirements with Application to Early Aspects

This paper introduces an information retrieval based approach for automating the detection and classification of non-functional requirements (NFRs). Early detection of NFRs is useful because it enables system level constraints to be considered and incorporated into early architectural designs as opposed to being refactored in at a later time. Candidate NFRs can be detected in both structured and unstructured documents, including requirements specifications that contain scattered and non-categorized NFRs, and freeform documents such as meeting minutes, interview notes, and memos containing stakeholder comments documenting their NFR related needs. This paper describes the classification algorithm and then evaluates its effectiveness in an experiment based on fifteen requirements specifications developed as term projects by MS students at DePaul University. An additional case study is also described in which the approach is used to classifying NFRs from a large free form requirements document obtained from Siemens Logistics and Automotive Organization