Stella: growing upward, downward, and outward [software review]

The author reviews Stella's modeling capabilities for both research and instruction. He describes the basic modeling tools using his student's quest as a simple, illustrative case study, exploring how these tools contribute to speed and efficiency in creating models for concept testing. He also examines some of Stella's broader research capabilities in the context of how they support and connect with more specific and scalable modeling systems implemented in high-end systems. Finally, he comments on Stella's range of educational applications. Stella (www.hps-inc.com) is a modeling application that can serve such needs, although it makes a relatively expensive scratch pad. Fortunately, it also provides other capabilities that add to its value as a productivity tool, just as a spreadsheet application lets you both build certain kinds of models and formulate a budget. Stella has several component toolsets, and its user interface is organized in layers. As such, the test of the application's total value is not just in its range of functionality but also in how well its toolsets and layers are integrated. The premise underlying Stella's design is that "systems thinking" is important for solving a wide class of problems and that there is a need for tools that support and cultivate this methodology.