Imagining what might be: why children underestimate uncertainty.

Children's well-documented tendency to behave as if they know more than they do about uncertain events is reduced under two conditions: when the outcome of a chance event has yet to be determined and when one unknown outcome has occurred but is difficult to imagine. In Experiment 1, in line with published findings, 5- and 6-year-olds (N=61) preferred to guess the unknown location of a known object when the object was in place rather than before its location had been determined. There was no such preference when the object's identity was unknown.

Agency affects adults', but not children's, guessing preferences in a game of chance.

Adults and children have recently been shown to prefer guessing the outcome of a die roll after the die has been rolled (but remained out of sight) rather than before it has been rolled. This result is contrary to the predictions of the competence hypothesis (Heath & Tversky, 1991 ), which proposes that people are sensitive to the degree of their relative ignorance and therefore prefer to guess about an outcome it is impossible to know, rather than one that they could know, but do not. We investigated the potential role of agency in guessing preferences about a novel game of chance.

Children's sensitivity to their own relative ignorance: handling of possibilities under epistemic and physical uncertainty.

Children more frequently specified possibilities correctly when uncertainty resided in the physical world (physical uncertainty) than in their own perspective of ignorance (epistemic uncertainty). In Experiment 1 (N=61), 4- to 6-year-olds marked both doors from which a block might emerge when the outcome was undetermined, but a single door when they knew the block was hidden behind one door. In Experiments 2 (N=30; 5- to 6-year-olds) and 3 (N=80; 5- to 8-year-olds), children placed food in both possible locations when an imaginary pet was yet to occupy one, but in a single location when the pet was already hidden in one.