Improving Stock-Flow Reasoning With Verbal Formats

Background. Stock-flow (SF) problems are ubiquitous in nature, ranging from the accumulation of water in a tub to the accumulation of CO 2 in the atmosphere. However, research on SF failure repeatedly demonstrates that people have severe difficulties understanding even the most basic SF problems. Purpose. This study tested the hypothesis that people’s understanding of SF problems depends on the presentation format used. Specifically, we expect SF failure to decrease when avoiding previously used scientific formats comprising coordinate systems and graphs, and SF problems are presented in verbal formats. Method. Participants ( N = 107) solved a range of different SF problems with experimentally varied presentation formats (verbal vs. graphic). We assessed fundamental understanding of graphs and graphical versus verbal production of stocks and in- and outflows. Results. Solution rates show that (a) SF failure is at least partially caused by specifics of the presentation format used previously; (b) fundamental misunderstandings in the construction of graphs can explain previous findings ; and (c) the majority of participants arrived at the correct solution when SF problems were presented verbally. Conclusion. The present study indicates that people are able to solve SF problems when they are presented in accessible formats . This result bears implications for simulation-based learning and assessment , and for the communication of SF problems.