Noname manuscript No. (will be inserted by the editor) The influence of cyclomatic complexity distribution on the understandability of xtUML models Nenad Uki´c · Josip Maras · Ljiljana Seri´cˇ Received: date / Accepted: date Abstract Executable software models formalize functional software requirements. This means that the understandability of software models is of paramount im- portance. In this paper, we investigate the influence of distribution of model cyclomatic complexity on the understandability of Executable Translatable UML (xtUML) models. We adapt traditional cyclomatic complexity metrics to differ- ent xtUML sub-models and present two different ways of measuring complexity distribution: horizontal, among elements of the same type, and vertical, among elements of different types. In order to test our hypothesis that cyclomatic com- plexity distribution influences the understandability of xtUML models, we have performed an experiment with student participants in which we have evaluated the understandability of three semantically equivalent xtUML models with different complexity distributions. Results indicate that a better distribution of cyclomatic complexity has a positive influence on model understandability. Keywords xtUML · understandability · cyclomatic complexity · distribution 1 Introduction Traditionally, software models are used in the initial stages of the software develop- ment process: for requirements analysis, documentation, or early design purposes. The first formal use of UML-based models in software development typically meant N. Uki´c Ericsson Nikola Tesla d.d. Poljiˇcka cesta 39 Split 21000 Croatia Tel.: +385-91-3655970 E-mail:
[email protected] J. Maras University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Ar- chitecture in Split (FESB), R. Boskovica 32, 21 000 Split, Croatia E-mail:
[email protected] Lj.