Conservation of length and the development of a size concept

The influence of the ability to conserve length in the development of a size concept was investigated in a series of two experiments. The inability to conserve length influences the perceptual bias of young children using the linear vertical dimension of objects as a salient cue in a paired comparison task when stimulus objects do not share a common baseline. When both stimulus position and attributed functional direction are involved, the latter is more influential in serving an orienting function. Sex differences suggest that females are more field dependent than males in the use of the vertical linear dimension as a cue in the judgment of "bigger" in a paired comparison task.