A case study of requirements quality analysis

Requirements analysis occupies a prominent part in the activities of a product life cycle. Out of the various aspects of the analysis, those related to the quality of requirements can have a large impact in the quality of the final product. Since requirements are first conceived as natural language expressions, and intensive use of automation is advised to keep project cost at reasonable level, it seems opportune to develop requirements analysis by means of natural language processing techniques. In spite of the scarce interest drawn by these issues within the industrial environment, the advantages of adopting natural language processing techniques to improve the quality of requirements are thought worth of repaying some research efforts, so the issue has been studied for years in the academic world and several solutions are proposed in literature. In this paper, a short survey of the existing solutions is presented and an approach that makes use of a model, a tool and a process to analyse the quality of requirements is proposed and compared. Then the results of applying the approach to the case study of requirements for train-control design, issued by the European Railway Agency, are reported and discussed. Also an industrial experience of a Service Centre about requirement analysis is shown and related application research issues are proposed.