Developmental changes in children's judgments of age.

Recent investigations employing drawings of human figures as stimuli have suggested that it is not until approximately age nine that children are able to judge age accurately. It was hypothesed that these results were influenced by the ambiguity of the drawings used, and the present study was designed to investigate children's judgments of age when more realistic stimuli (photographs) were employed. The primary focus of the investigation was on developmental changes in judgments correlating people's age with their physical size. Stimuli consisted of photographs of males and females characterizing four age levels: infant, child, adolescent, and middle-aged adult. Each figure was reproduced in two sizes. Using a paired-comparison procedure, children from ages three through nine years (16 at each age level) were presented with either the male or female stimulus sets by either a male or female experimenter. The ability to judge age correctly increased linearly with age. Accuracy improved from 47% at age three to 59% at age six and to 100% at age nine. Errors were primarily due to basing age judgments on size. Results were discussed in terms of (a) adequacy of stimuli in age perception studies and (b) cognitive development within a Piagetian framework.