Proceedings of the Annual Meeting of the Cognitive Science Society

Proportional reasoning is a widespread form of quantitative thinking. Proportion also provides an opportunity to investigate the mechanisms that determine what algorithms we use to reason about quantity. Prior work shows that the visual features of proportional information (e.g., whether it is depicted continuously vs. discretely) influence whether thinkers adopt more optimal or suboptimal strategies. However, these studies investigated strategy selection when all proportions were presented in a single visual format. We hypothesize that comparing proportions across formats (continuous "blobs" vs. discrete dot arrays) will discourage suboptimal numerator strategies by making numerical information unavailable for comparison across proportions and encourage using more reliable part-whole relations within each proportion. Here, we report a study that tested this hypothesis. Participants completed a proportion comparison task where they compared proportions either within- or across-formats. Results support the hypothesis that cross-format comparison deters suboptimal numerator strategies and promotes more optimal part-whole quantitative reasoning strategies.