Revealing Conceptual Difficulties when Interpreting Histograms: An Eye-Tracking Study

Many people misinterpret histograms. The conjecture is that some of these misinterpretations emerge from the application of interpretation strategies associated with case-value plots. To investigate this, eye-movement data were collected from six university students solving questions on histograms and case-value plots. Analysis of gaze data and cued retrospective verbal reports showed that participants seemed to use a histogram interpretation strategy, a case-value plot interpretation strategy or an elimination strategy. Several participants appeared to use a single preferred strategy without distinguishing between the type of graphs at stake. As conjectured, some participants applied a casevalue plot strategy also to histograms. In addition, analysis of gaze data and verbal reports suggest that more experienced participants abandoned their nitial strategy when necessary.