System and Software Requirements Validation through Inspections: Constructive Reading and Mining Requirements from Natural Language Requirements Documents

Abstract

Defects introduced early in the effort to engineer a system due to poorly identified requirements are generally seen as a major factor leading to high system and software costs, especially if the defective requirements are undetected until later development phases in the lifecycle of engineering a system. In software development, inspection methods have been particularly successful when applied to code inspections, but have often been substantially less effective when they are applied to natural language requirements specifications. Yet, the ultimate savings due to error detection, diagnosis, and correction before a trial system is produced are generally great. This paper addresses the problem of improving requirements inspections by exploring foundational issues, such as the ability of inspectors, the degree that skill is present as a stable and determining factor, and whether defect detection is influenced by intrinsic differences in difficulty of detection among defects. A new inspection technique, denoted Constructive Reading Inspection Process (CRIP), was developed and used to explore requirements inspection, which involves extracting the conceptual entities and their interrelationships as opposed to looking solely for defects. Inspections of phase products in software development is a best-practice in systems and software engineering, however reading inspection of natural language requirements is less productive than the same practices applied to code. Our study of reading inspections reveals issues largely overlooked in the past which suggest that low yields can be partly accounted for by cognitive factors, lack of uniform expectations, and the character of ordinary reading. The Constructive Reading Inspection Process focuses on revealing and illuminating the conceptual entities and inspecting those; thereby shifting the implied operational metaphor from fishing (looking for defects) to mining (exhuming and polishing entities). This paper describes the process, its use, and provides a preliminary evaluation of its effectiveness.