Similarity by feature creation: Reexamination of the asymmetry of similarity

We developed a computational model of similarity judgment in problem-solving contexts. The model first attempts to transform an object to another using the knowledge of the domain, the strategy, and the goal. If the transformation succeeds, new feature about transformability is created. A similarity of an object to another is computed, based on the created features. If the model fails to create a new feature, it computes a similarity by feature comparison in the same way as the contrast model. An important prediction of the model is that the asymmetry of similarity judgments is caused by the directionality of the problem-solving skills. We examined the model’s prediction. The material was the Tower of Hanoi puzzle. Subjects were required to rate the similarities of one state to the goal as well as those of the goal to a state. In experiment 1, we taught one group of subjects the ‘move-pattern strategy’ that induced learners to acquire highly directional skills, and compared their judgments with those by naive subjects. The asymmetry was observed only in the judgments by the trained subjects. The second experiment showed that the results of the experiment 1 could not be reduced to the ‘prototypicality’ of the goal.