“STOCK AND FLOW DIAGRAMS” FOR DEEPER LEARNING OF CHANGE

Decision-makers and people in general are preoccupied with how things change through time. Hence, change is an important topic to teach. However, numerous studies show that people have problems understanding even very simple dynamic systems. Therefore, to deal with dynamic systems, people rely on experience or analogies. But, experience can be missing or misleading when conditions change, and analogies may reflect surface similarities and not underlying cause and effect relationships. To become aware of such pitfalls and to foster deeper learning, this paper proposes the use of “stock and flow diagrams” (SFDs) combined with simulations. The paper makes a theoretical argument for the benefits of SFDs, and makes use of sample models to illustrate. SFDs are more intuitive and easier to understand than conventional differential equations. While SFDs operate with only four different symbols, differential equations require basic knowledge and familiarity with a mathematical language that few people are comfortable with. SFDs give overviews of systems that are easily lost in sets of coupled equations. The sample SFDs illustrate the close similarity of analogous systems from alcohol consumption, climate change, and fishery management to oscillating springs and rocket science. Once a student understands one of these systems, the diagrams help them understand the others. Hence, SFDs are ideal for interdisciplinary problems. Sample models also help explain why some policies fail and others produce desired results. Recently, easy to use new software has made it easy to produce teaching material or learning environments involving SFDs, see e.g. https://exchange.iseesystems.com/public/erling/learning-with-stock-and-flow-diagram-funnel/index.html#page1 . This method is ideal for distance learning and for flipped classroom teaching.