An illustrative societal model for classroom computer simulation

A flexible classroom tool is designed to illustrate various aspects of complex systems and models of such systems. The tool consists of a model, a computer program for simulation using the model, and a classroom curriculum that describes games and exercises for use with the program. The subject matter of the model is the system of harvesting, converting, transporting, and consuming natural resources in a hypothetical society. Data structures and algorithms for implementing a computer simulation using the model are specified in a pseudo-Pascal format. The design steps and features of a curriculum for this tool are proposed, as well as steps for implementing and testing in a classroom environment.

The model design is guided by the foreknowledge of the final goals. These goals distinguish this study from more "traditional" computer-simulated model designs by stressing behavior illustration rather than behavior prediction. Both the specific model and the process of modelling are illustrated.

The desire for "flexibility" includes allowing the teacher to specify initial values, rules of interaction, which values may be interactively entered, and the scope of the system to be simulated, prior to the class activity. Flexibility also includes allowing students to choose interactively between various forms of output while the simulation is running. Each change in specifying input variables or output functions effectively changes the model, so this design is really of a "class" of models rather than of a single model. The computer simulation implements the selection of one or more models from the class.

Particular design choices reflect the goal of an illustrative rather than a predictive simulation. A discrete -time and -event model is favored for allowing a gaming, interactive classroom format that is accessible to non-sophisticated users. A data structure is designed to allow components to be specified either by input or noninput state variables. Algorithms for selecting which way to specify components and for selecting output functions (i.e., for selecting the model to use from the class of models) are described.