Enhancing equivalence class formation by pretraining of other equivalence classes

This study investigated how the learning of one set of equivalence classes enhances the learning of new equivalence classes. Fifty-two undergraduate students were divided into four groups. Subjects in Group 1 received no pretraining. Using the simple-to-complex procedure followed by incremental expansion of class size, subjects in Groups 2, 3, and 4 learned 3-, 4-, and 5-member equivalence classes, respectively. After pretraining, two new 3-member equivalence classes were established by the concurrent training of all baseline relations and the concurrent presentation of all emergent relations probes to assess class formation (the simultaneous protocol). With no pretraining, 58 % of subjects formed the new classes under the simultaneous protocol. After pretraining of the 3-, 4-, and 5-member classes, the new classes were formed by 62, 85, and 100 % of the subjects, respectively. Pretraining of 4- and 5-member classes produced a small increment in the percentage of subjects who showed the immediate emergence of the new classes. Pretraining of the 5-member classes produced a large increment in percentage of subjects who formed classes with repeated testing. Thus, pretraining influenced immediate and delayed emergence of equivalence classes. With no pretraining, during the tests used to assess the formation of the new classes, 12 % of subjects showed disruption of baseline performances, relational responding produced by symmetry probes was lower than that produced by baseline relations, and very low levels of relational responding were evoked by 1-node probes. These data demonstrated the effects of nodal distance. Pretraining did not ameliorate the disruption of baseline performances. Pretraining of 4- and 5-member classes produced moderate increments in the relational responding evoked by symmetry probes. Pretraining of 5-member classes produced large increments in the relational responding evoked by 1-node probes. This paper was prepared with the support of Contract MDA903-90-C-132 from th