title: High Numerates Count Icons and Low Numerates Process Large Areas in Pictographs: Results of an Eye-Tracking Study.
abstract: In two experiments, we investigated the influence of numeracy on individuals' information processing of pictographs depending on numeracy via an eye-tracker. In two conditions, participants from the general population were presented with a scenario depicting the risk of having cancer and were asked to indicate their perceived risk. The risk level was high (63%) in experiment 1 (N = 70) and low (6%) in experiment 2 (N = 69). In the default condition, participants were free to use their default strategy for information processing. In the guiding-toward-the-number condition, they were prompted to count icons in the pictograph by answering with an explicit number. We used eye-tracking parameters related to the distance between sequential fixations to analyze participants' strategies for processing numerical information. In the default condition, the higher the numeracy was, the shorter the distances traversed in the pictograph were, indicating that participants counted the icons. People lower in numeracy performed increased large-area processing by comparing highlighted and nonhighlighted parts of the pictograph. In the guiding-toward-the-number condition, participants used short distances regardless of their numeracy, supporting the notion that short distances represent counting. Despite the different default processing strategies, participants processed the pictograph with a similar depth and derived similar risk perceptions. The results show that pictographs are beneficial for communicating medical risk. Pictographs make the gist salient by making the part-to-whole relationship visually available, and they facilitate low numerates' non-numeric processing of numerical information. Contemporaneously, pictographs allow high numerates to numerically process and rely on the number depicted in the pictograph.
authors.affiliation: ETH Zurich, Institute for Environmental Decisions (IED), Consumer Behavior, Zurich, Switzerland.
authors.forename: Christina
authors.initials: C
authors.lastname: Kreuzmair
authors.affiliation: ETH Zurich, Institute for Environmental Decisions (IED), Consumer Behavior, Zurich, Switzerland.
authors.forename: Michael
authors.initials: M
authors.lastname: Siegrist
authors.affiliation: ETH Zurich, Institute for Environmental Decisions (IED), Consumer Behavior, Zurich, Switzerland.
authors.forename: Carmen
authors.initials: C
authors.lastname: Keller
keywords: Eye tracking; information processing strategies; medical risk communication; numeracy; pictograph