Case studies in software process modeling with system dynamics

Litton's Guidance and Control Systems (GCS) Division has been using system dynamics to create mostly small-scale models for investigating managerial process issues and supporting personnel training. At the project level, these include models for planning specific projects, studying Brooks's Law and hiring issues, an interactive earned value model, requirements volatility and a detailed peer review model. The perspective of some of the models has been at a multi-project or departmental level including domain learning, product-line reuse processes and resource contention among projects. Insights provided by the models have supported decision-making at different levels and helped galvanize process improvement efforts. The training applications have added spark in classes and improved overall learning. The models encapsulate collective knowledge of modeling participants, and support organizational learning. By examining the models and simulated behavior, managers share a process vision and can discuss issues against the common models. The models have helped managers understand the key factors in complex scenarios. Knowledge of the interrelated technical and social factors coupled with simulation tools has enabled GCS to improve their planning and management processes. Modeling is also used to support training of software managers and leads. Topics including earned value techniques, productivity estimation, requirements volatility effects and extrapolation of project tracking indicators have been presented with simulation models. Some of these are ‘flight training’ scenarios that the students interact with to practice project control. Though we are in the early stages of many of these efforts, they will be followed through and reported on at a later time. This paper describes our introductory experiences and plans for the future. Copyright © 2000 John Wiley & Sons Ltd