Abstract for: Does Modification of Representation Format Affect Stock–Flow Thinking?
Stock–flow systems are poorly understood even though we are faced with them in many, sometimes very important domains. Several studies found that only few participants solved stock–flow tasks correctly and that modifications of the representation format (e.g. changing the flow graphs) did not improve performance. In the present study, we modified the representation in a more extreme way. Because it seems people have difficulty distinguishing between stocks and flows, we wanted to simplify the transformation of flows into stock. We created teaching pictures where the flows were presented as stocks per time unit. We analyzed if such a representation improved stock–flow performance. Participants had to solve three tasks in different representation formats (tub, bus, and line graph). Regression analyses revealed differences in performance. The modified representation conditions led to a better stock–flow performance (R˛ = .389, partial correlations: .557, p < .001 (tub), .498, p < .001 (bus)). To test for transfer, all participants had to work on two additional tasks presented as line graphs. The modified representation groups did not solve the additional tasks better than the line-graph group. To summarize, the teaching pictures simplified solving stock–flow tasks but transfer did not occur.