Computer simulations are widely used in physics instruction because they can aid student visualization of abstract concepts, they can provide multiple representations of concepts (graphical, trajectories, charts), they can approximate real-world examples, and they can engage students interactively, all of which can enhance student understanding of…

Replicates an earlier study that used videotapes to examine the types of errors made by novice economics students in graphic analysis of a simple supply-demand problem. Further explores the issue by improving the framework for analyzing errors and documenting some methods used by novice groups to correct errors. (MJP)