Subjective organization of U.S. presidents

College students appear to subjectively organize U.S. presidents into three groups and to use this organization to help them learn new information. Results of a paired comparison task in Experiment 1 suggested that subjects organized the presidents into Founding Fathers (Washington through John Quincy Adams), post-World War II presidents (Truman through Reagan), and noncontemporary presidents (Jackson through Franklin Roosevelt). This hypothesized organization was tested in Experiment 2 by presenting subjects with several lists with alternative organizations of the presidents. Difficulty of learning classifications of particular presidents within each list was predicted on the basis of the relation between that president's classification in the list and in the hypothesized preexisting organization. Instances where the preexisting and new classifications were consistent both for the particular president and for all other members of the group were easiest to learn. Instances where the particular president's classification was consistent but where some other presidents in the group were classified differently were of intermediate difficulty. Instances where neither the individual president's classification nor that of the entire group were consistent were most difficult. The results provided converging evidence for the hypothesized subjective organization of the presidents and also demonstrated the usefulness of a method that may be applicable to testing subjective organizations in a wide variety of other areas.