Experimental Comparison of the Comprehensibility of a UML-based Formal Specification versus a Textual One

The primary objective of software specification is to promote understanding of the system properties between stakeholders. Specification comprehensibility is essential particularly during software validation and maintenance as it permits the understanding of the system properties more easily and quickly prior to the required tasks. Formal notation such as B increases a specification’s precision and consistency. However, the notation is regarded as being difficult to comprehend due to its unfamiliar symbols and rules of interpretation. Semi-formal notation such as the Unified Modelling Language (UML) is perceived as more accessible but it cannot be verified systematically to ensure a specification’s accuracy. Integrating the UML and B could perhaps produce an accurate and approachable specification. This paper presents an experimental comparison of the comprehensibility of a UML-based graphical formal specification versus a purely textual formal specification. The measurement focused on the efficiency in performing the comprehension tasks. The experiment employed a cross-over design and was conducted on forty-one third-year and masters students. The results show that the integration of semi-formal and formal notations expedites the subjects’ comprehension tasks with accuracy even with limited hours of training.