Explaining Scale Error
In this study, we examined an interesting phenomenon known in the literature as "scale error". Scale error occours when children (or sometimes even adults) perform actions with objects even if the size of the tool makes it unsuitable for that purpose. In this study we aimed to support the view that scale error occurs not as a consequence of the immaturity of the perceptual system, but as a result of cultural learning.
In the first part of the study, three-year-old children learned the function of three new objects (eg, a certain type of chopstick was used to sound a whistle in a box). In the next phase, the children had the opportunity to try the objects they had seen but with some important changes to the first phase. In one case, the object in the demonstration was replaced by a tool that was identical to everything in the demonstration except its size, so in this case, it was too large to perform the original function effectively. In another case, this oversized object was also colored differently to distinguish the new object from the original one, even if the children had a problem with size perception. Along with the modified objects, each child had a tool that they had not seen before and was suitable for performing the original function. Our question was very simple: Do children recognize that the familiar but oversized object is unfit for the purpose this time, and will they choose a new but appropriate tool or will they stick to the familiar one?
Our results show that in half of the cases the children stuck to the familiar object, even if it was not only of a different size but also of a different color. This result suggests that scale errors are not only about children having difficulty to judge the size (because we have gotten the same results for different colored objects), but rather that during demonstration children immediately develop the mental concept of the object category, and when the tool is identified as a member of the category they apply the previously acquired knowledge.
These results are complemented by a third version of the experiment, in which we did not demonstrate the function of the objects. We were curious to find out whether the children would be able to select the right tools. We found that the children involved in this version used the right objects in the vast majority of cases.