What's in a Mental Model of a Dynamic System? : On the Conceptual Structure and Approaches to Model Comparison

This paper deals with the representation of mental models of dynamic systems (MMDS). The notion of mental model has always been fundamental in system dynamics, and 10 years ago, a specific definition was introduced. However, no conceptual model of what MMDS contain was offered. Since then, two assessment and comparison methods from other fields have been borrowed, one trying to express the distance, the other expressing the closeness. The question is if they are equivalent in procedure and results, and how they satisfy specific needs of system dynamics. Two exemplary models are compared with each of the methods, which are found to de different in procedure and in results they produce. Additionally, they ignore the feedback loop concept. So a conceptual model for the structure of MMDS and a method for comparing are proposed; application to the exemplary models shows some alleged advantages. A preliminary conclusion is that more discussion and comparative work are needed.