The Effects of Delayed versus Simultaneous Matching-to-Sample on Equivalence Classes Reorganization

The delayed matching-to-sample (DMTS) procedure enhances equivalence class formation when compared to the simultaneous matching-to-sample (SMTS). However, studies have shown different outcomes for classes reorganization. In this study, we investigated the effects of DMTS and SMTS for reorganizing classes that were initially established using DMTS. Twenty undergraduate students learned conditional discriminations AB, AC, and AD using a DMTS (2s). After this training, equivalence test trials assessed the formation of two classes (A1B1C1D1; A2B2C2D2). Participants were then assigned to two groups, DMTS Group and SMTS Group. All participants performed a reversed AD training (A1D2; A2D1) and a baseline review containing AB, AC and reversed AD trials, but under different MTS procedures according to their respective groups. Eight participants in DMTS group and seven in SMTS group reorganized the classes (A1B1C1D2; A2B2C2D1). The percentage of correct responses in the reorganization tests was not significantly different between groups. Procedural features were examined to explain why DMTS improves class formation but not class reorganization.