SIMILARITY AND PROPERTY EFFECTS IN INDUCTIVE REASONING

Three experiments investigated the proposal that inductive inferences about different properties depend on different measures of similarity. In Experiments 1 and 2, Ss were given the premise that a category of animals has some property and judged the probability that another cate gory of animals also has that property. Ss made the strongest inferenc es when the kind of property (anatomical or behavioral) corresponded t o the kind of similarity between the animal categories (anatomical or behavioral). These results cannot be explained in terms of a single me asure of similarity underlying induction. In Experiment 3, Ss rated th e similarity of animal pairs with respect to anatomy or behavior. Regr ession analyses showed that both behavioral and anatomical similarity influenced behavioral inferences, but only anatomical similarity influ enced anatomical inferences.