Application of Graph Grammars in an Educational Software Engineering Game: A Case Study in Pragmatic Adoption

Abstract

This paper introduces an approach to modeling software project dynamics using an attributed graph grammar formalism. A project situation is modeled and presented to a "player" who is supposed to act as project manager of a simulated project. Events and internal processes of the simulated project are modeled using a custom-designed formalism that integrates attributed graph grammar concepts with a quantitative simulation mechanism resembling System Dynamics. Both ingredients were pragmatically selected and blended based on (1) their comparative simplicity, (2) their expressive power, and (3) their intuitive appeal for bridging the cognitive gap between real-world software engineering experiences and an executable simulation model. This modeling formalism was applied in the SESAM educational software engineering game. The modeling formalism was supported by a family of graphical SESAM editors. Resulting models could be animated and served as simulated projects in the game runs. SESAM was applied in graduate courses on software project management at the University of Stuttgart. Experiences with the modeling approach are reported. The design history and design rationale that led to using graph grammars as the underlying formalism are described and discussed. The design of the SESAM modeling formalism is presented as an (involuntary) case study in adopting a graph grammar approach.