Proceedings of the Annual Meeting of the Cognitive Science Society

Modern society frequently requires that we express our sub-jective senses in objective, shared formal systems; this en-tails mapping multiple internal variables onto a common scale.Here we ask whether we accomplish this feat in the case ofestimating number by learning a single mapping between ex-plicit numbers and one integrated subjective estimate of nu-merosity, or if we separately map different perceptual featuresonto numbers. We present people with arrays of dots and askthem to report how many dots there are; we rely on the sys-tematic under/overestimation of number at higher quantities toestimate error in the mapping function. By comparing how thiserror changes over time, as the mapping fluctuates for differentvisual cues to numerosity, we can evaluate whether these cuesshare a single mapping, or are mapped onto number individu-ally. We find that area, size, and density all share a commonmapping, indicating that people obtain a unified subjective es-timate of numerosity before mapping it onto the formal numberline.