Surfacing ambiguity in natural language requirements

In industrial requirements engineering (RE), natural language is the most frequently used representation to state the requirements that are to be met by information technology products or services. Natural language is universal, flexible, and wide-spread, but unfortunately also inherently ambiguous. Even worse, often neither customers nor software develirements. This thesis presents the ADTD approach, which allows developing techniques for detecting ambiguities in natural language requirements on the basis of existing and industrially proven techniques, namely checklists, scenario-based reading, and agendas. A technique for detecting ambiguities must be tailored to a particular RE context to be effective, because RE-specific ambiguities depend heavily on the context in which an RE process takes place. For this purpose, the ADTD approach provides heuristics to investigate meta-models, which capture information about an RE context. These heuristics help identify the RE-specific types of ambiguities that are typical for the particular RE context. A set of ambiguity detection techniques for the domain of embedded systems was developed using the ADTD approach to show its feasibility. To quantify the benefits of the ADTD approach, the resulting techniques were empirically validated in five experiments. The goals were (1) to validate that the investigation of metamodels pays off in terms of higher efficiency of the resulting technique and (2) to show that our ambiguity detection techniques are superior to existing ones. From a practitioner's perspective, a set of validated techniques for detecting ambiguities is provided, which allow improving current RE processes of different maturity. The ADTD approach is available for developing additional techniques if the provided ones do not fit the situation at hand. From a researcher's perspective, new insights are provided on the problems that defects, and ambiguities in particular, cause when semi-formal or formal specifications are developed from an informal statement of requirements. Also, the thesis provides a comprehensive understanding of the various facets of ambiguity in RE. This understanding clarifies the currently ambiguous use of the term in the literature

Ten years of REFSQ: A quantitative analysis

In its first ten editions, the REFSQ workshop has published over 150 papers on various aspects of Requirements Engineering. In this paper, we apply statistical lexical analysis techniques to this large corpus, in order to characterize the main topics and trends that have emerged from ten years of research in this area. The results provide both an historical perspective (and some lesson) on the evolution of favored research topics, as well as suggestions for the future, in particular about topics that have not been adequately addressed so far