Role of an abstract order schema in conceptual judgment.

Ss performed same-different judgments for which order information was logically irrelevant. In Experiments 1 and 2, the stimuli for the judgment task were derived from an ordered set of concepts from long-term memory (U.S. presidents ordered on the dimension of historical time); in Experiments 3 and 4 the stimuli were derived from two ordered sets of concepts. In the stimulus set for each experiment, there were several associate phrases for each concept and the task was to judge whether the phrases were paired with the same concept (Experiments 1, 2, and 3) or the same ordering (Experiment 4). The time to respond "different" decreased with the ordinal distance between the concepts even when the concepts belonged to different orderings. It is concluded that same-different judgments are based in part on amodal order information (i.e., not tied to any particular dimension). Two models of the implicated order schema are proposed and tested.