Based on the diagnosticity principle (Tversky, 1977), the systematicity principle (Gentner, 1983) is interpreted as that the deep structure of object has higher diagnostic value than the surface features in analogical reasoning. However, it is not clear that which one of the object's features corresponds to each of the surface and the deep structure in Tversky's research. Another question is whether the diagnostic value of the deep structure is judged higher than that of the surface or not when the diagnostic value of the object's feature is determined by a presentational factor such as the combination of base analogues. In the present paper, we conducted 2 experiments to analyze the effect of presentational factor on the diagnostic value of a given feature using the competitive design in the context of the diagnosticity principle.
In experiment 1, 82 subjects read only one judicial precedent and composed a sentence of the target trial. The results supported the validity of the systematicity principle except the subjects' plausibility judgements for their sentence predictions. In experiment 2, 60 subjects read 3 judicial precedents and judged the similarity with the target trial to compose a sentence. A diagnosticity effect was found in the subjects' similarity judgments and also in their importance judgements of the target trial's superficial features. The subjects judged the base-to-target similarity higher with the structurally dissimilar base than the structurally similar base, and their sentence predictions did not match the sentence of the original trial. The results did not fully support the validity of the systematicity principle.
