Beatriz Bernárdez

Verifying software requirements with XSLT

In this article, we present an approach for the automatic verification of software requirements documents. This approach is based on the representation of software requirements in XML and the usage of the XSLT language not only to automatically generate requirements documents, but also to verify some desired quality properties and to compute some metrics. These ideas have been implemented in REM, an experimental requirements management tool that is also described in this paper.

Empirically Driven Use Case Metamodel Evolution

Metamodel evolution is rarely driven by empirical evidences of metamodel drawbacks. In this paper, the evolution of the use case metamodel used by the publicly available requirements management tool REM is presented. This evolution has been driven by the analysis of empirical data obtained during the assessment of several metrics–based verification heuristics for use cases developed by some of the authors and previously presented in other international fora. The empirical analysis has made evident that some common defects found in use cases developed by software engineering students were caused not only by their lack of experience but also by the expressive limitations imposed by the underlying use case metamodel used in REM. Once these limitations were clearly identified, a number of evolutionary changes were proposed to the REM use case metamodel in order to increase use case quality, i.e. to avoid those situations in which the metamodel were the cause of defects in use case specifications.

A controlled experiment to evaluate the effects of mindfulness in software engineering

Context. Many reports support the fact that some psycho--social aspects of software engineers are key factors for the quality of the software development process and its resulting products. Based on the experience of some of the authors after more than a year of practising mindfulness---a meditation technique aimed to increase clearness of mind and awareness---we guessed that it could be interesting to empirically evaluate whether mindfulness affects positively not only the behaviour but also the professional performance of software engineers. Goal. In this paper, we present a quasi--experiment carried out at the University of Seville to evaluate whether Software Engineering & Information Systems students enhance their conceptual modelling skills after the continued daily practice of mindfulness during four weeks. Method. Students were divided into two groups: one group practised mindfulness, and the other---the control group---were trained in public speaking. In order to study the possible cause--and--effect relationship, effectiveness (the rate of model elements correctly identified) and efficiency (the number of model elements correctly identified per unit of time) of the students developing conceptual modelling exercises were measured before and after taking the mindfulness and public speaking sessions. Results. The experiment results have revealed that the students who practised mindfulness have become more efficient in developing conceptual models than those who attended the public speaking sessions. With respect to effectiveness, some enhancement have been observed, although not as significant as in the case of efficiency. Conclusions. This rising trend in effectiveness suggests that the number of sessions could have been insufficient and that a longer period of sessions could have also enhanced effectiveness significantly.

An experimental replication on the effect of the practice of mindfulness in conceptual modeling performance

Context: Mindfulness is a meditation technique aimed to increase clearness of mind and awareness. In the 2013–2014 academic year, an experiment was carried out to test whether the practice of mindfulness during 4 weeks improved or not the conceptual modeling performance using UML class diagrams of 32 second–year students of Software Engineering at the University of Seville. Objective: An internal replication with some changes in the original design was performed in the first semester of the 2014–2015 academic year in order to confirm the insights provided by the original study and increase the confidence in its conclusions. The sample were 53 students with the same profile than in the original study. Method: Half the students (27 subjects) practiced mindfulness during 6 weeks, while the other half (26 subjects), i.e. the control group, received no treatment during that time. All the students developed two conceptual models using UML class diagrams from a transcript of an interview, one before and another after the 6 weeks of mindfulness sessions, and the results were compared in terms of conceptual modeling effectiveness and efficiency. Results: The results of both experiments were similar, showing that the practice of mindfulness significantly improves conceptual modeling efficiency. Regarding conceptual modeling effectiveness, an improvement is observed in practice, but the analysis shows that such improvement is not statistically significant. After a reanalysis of data, consistent results have also been obtained. Conclusion: After a replication that leads to the same conclusions as the original study, the adequacy of the original experiment is confirmed and the credibility of its results is increased. Thus, we can state that the practice of mindfulness can improve the efficiency of Software Engineering students in the development of conceptual models, although further experimentation is needed in order to confirm the results in other contexts and other Software Engineering activities different from conceptual modeling.