Proceedings of the Annual Meeting of the Cognitive Science Society

Throughout development, humans infer unobserved properties of the objects they encounter. However, it is often ambigu-ous whether these inferences result from category-based reasoning or overall similarity to previously observed objects. Inthis study, we examined inferences about hidden properties in four-year-old children (N=36) and adults (N=44). We taughtparticipants three categories of artificial creatures. Each category had one critical feature, where one of its variations wasmore common to members of the category, while the other was more common overall. We found that, on average, bothgroups used within-category frequency to predict the value of an unseen critical feature. However, individual differencesrevealed distinctions between the groups. While adults who used within-category frequency for critical items used overallfrequency for other items, this correlation was qualitatively reversed in children. This suggests that some children weresensitive to category knowledge when predicting unseen features, but others likely used a novelty heuristic.