Figure 5.

Modeling predictions and results. (A) The best-fitting parameter values of the Full model show that adults and children do not differ in the learning rate (α) or the level of random exploration (β ), but that children show a greater relative influence of systematic exploration (ϕ ) than adults. (B) Parameter estimates from the reduced model (with no systematic exploration) suggest that if systematic exploration is not accounted for children appear to be more random (indicated by lower β ), highlighting the importance of including systematic exploration in understanding children’s choices. Vertical bars represent the medians (solid) and means (dashed). (C) The hazard rates of choices, which is the probability of choosing an option given the amount of time since it was last chosen, demonstrates a critical difference in the two single-process models’ predictions. The Lag model predicts an increasing probability of picking an option the longer it’s been since it was last selected. Predictions were produced from simulations using best-fitting parameters from children best-fit by each model. (D) The proportions of participants best-fit by the Value, Lag, and Spatial uncertainty (Exp. 2) models are plotted. All adults were value-based. About half of children relied on choice lag when all options were uncertain (Exp. 1) and most relied directly on uncertainty when it was concentrated on a single option (Exp. 2), but note that this includes both uncertainty seekers and uncertainty avoiders.