Using pictograms improves the understanding of Stock-Flow Systems

Abstract

We examined if we could improve performance in so-called Stock- Flow Systems (SF-systems). SF-systems are dynamic systems, which consist of a stock and two flows – the inflow and the outflow. The stock changes depending on the flows’ patterns. Many persons have problems understanding these systems (Sterman, 2002). Up to now, only one modification of the flows’ representation format led to rather strongly enhanced SF-performance: using pictograms instead of line graphs (Brockhaus, Arnold, Schwarz, & Sedlmeier, 2013). The present experiment analyzed if pictograms led to better performance when the SF-task was somewhat changed; this time, we focused on basic SF-understanding. Additionally, it analyzed, if further modifications of the diagram – emphasizing the distinction of the two flows and emphasizing the calculated difference of inflow minus outflow – could improve SF- performance. Results showed, the effect was smaller, and participants working on pictograms only solved about 50% or less of the tasks correctly. However, using pictograms improved SF-performance again.