THE ROLE OF HYPOTHESIS ARRAYS IN SCAFFOLDING 3D VISUALIZATIONS: AN EYE-TRACKING STUDY

The exploration of large professionally collected data sets is important in the practice of geoscience. However, being able to visualize and interpret such data sets can be difficult for students, especially when the data represent a 3D volume. It is a pedagogical challenge to scaffold students’ data exploration without giving them step-by-step instructions. One promising approach, investigated in this study, is to provide students with an array of candidate hypotheses which they can potentially use to organize their data exploration, much as multiple working hypotheses can help direct an expert’s exploration of new data.

Study participants were 26 undergraduates enrolled in an introductory environmental science course. Students were asked to describe and interpret visualizations of Mediterranean salinity data while thinking aloud in response to guiding questions and being eye-tracked. In a 2D task, half of the students were provided with a verbal hypothesis array, outlining four possible interpretations of the elevated salinity and E/W salinity gradient of the Mediterranean, and asked to pick the correct interpretation. The other students made their interpretation without the hypothesis array. In a 3D task, all students were provided with a pictorial hypothesis array outlining four possible interpretations of the salt tongue west of Gibraltar, and asked to pick the correct interpretation before and after the presentation of three vertical data profiles.

Findings suggest hypothesis arrays are useful ways to scaffold student interpretation. A majority of students adjusted their initial interpretation of a phenomenon when presented with conflicting data; however, only 39% switched to the correct answer. Patterns of switching will be discussed. While no students chose a response option incompatible with data on the 2D task, 15% of students chose an incompatible response option on the 3D task, suggesting 3D tasks are more difficult. A range of student eye movement patterns were identified, including the duration and order of attention, and the coordination among map data, profile data, and the hypothesis array. Students differed in how methodically they gathered information from the multiple sources. The relationship among eye movement patterns, spatial ability, and performance on task will be discussed.