Compositionality and statistics in adjective acquisition: 4-year-olds interpret tall and short based on the size distributions of novel noun referents.

Four experiments investigated 4-year-olds' understanding of adjective-noun compositionality and their sensitivity to statistics when interpreting scalar adjectives. In Experiments 1 and 2, children selected tall and short items from 9 novel objects called pimwits (1-9 in. in height) or from this array plus 4 taller or shorter distractor objects of the same kind. Changing the height distributions of the sets shifted children's tall and short judgments. However, when distractors differed in name and surface features from targets, in Experiment 3, judgments did not shift. In Experiment 4, dissimilar distractors did affect judgments when they received the same name as targets. It is concluded that 4-year-olds deploy a compositional semantics that is sensitive to statistics and mediated by linguistic labels.