Comparing delayed matching to sample with three variations of the training‐ <scp>IRAP</scp> for establishing derived relations
A 2-second training-IRAP beats delayed matching for building new stimulus classes in typically developing learners.
01Research in Context
What this study did
The team compared four ways to teach new stimulus classes to college students.
They pitted the old standby—delayed matching-to-sample with a 2-second delay—against three tweaked versions of the training-IRAP.
All learners started from scratch and the study counted who formed the new classes and how many training blocks it took.
What they found
More students reached mastery with the modified training-IRAP formats than with delayed matching.
The IRAP versions that kept the 2-second pause needed fewer practice rounds to get the same result.
How this fits with other research
Harte et al. (2021) first showed that a training-IRAP could flip already-learned relations; Silvestre et al. (2026) now show it also builds brand-new classes faster than the classic method.
Taras et al. (1993) warned that any delay must reliably signal “reinforcer soon”; the 2-second gap used here fits that rule and may explain the speed edge.
Vaidya (2026) predicts fresh IRAP tweaks are coming—this study delivers one that is ready to use today.
Why it matters
If you run equivalence-based instruction, swap your usual delayed matching trials for a 2-second training-IRAP format. You will likely see learners hit mastery in fewer blocks, saving valuable table time. Try it next time you teach coin names, sight words, or any new category.
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02At a glance
03Original abstract
A common method for studying derived relations is the matching‐to‐sample (MTS) preparation. However, certain aspects of its training format potentially hinder the emergence of new relations. The training version of the implicit relational assessment procedure (training‐IRAP) may present an alternative. Our primary objective involved comparing the effectiveness of delayed MTS(2s) and training‐IRAP procedures on participant yield. The secondary objective involved comparing mean number of training blocks per procedure. Given additional components in the standard training‐IRAP not found in MTS, changes were made to the former, producing the modified training‐IRAP and delayed modified training‐IRAP(2s). Sixty‐eight typically developing students participated in a between‐subjects design. Two classes comprising five abstract stimuli were employed. Yield was analyzed at three levels, 91.67, 83.33, and 79% correct responses, with at least 87.5% correct responses at baseline mixed‐block maintenance. All participants maintained baseline criterion during tests. At the three levels of analyses, the modified versions of training‐IRAP produced higher yield, followed by DMTS(2s) and then the standard training‐IRAP. Mean number of blocks to complete training phases was lowest for the delayed MTS(2s) and delayed modified training‐IRAP(2s) groups. Limitations and implications of the findings toward greater precision, scope, and depth in conceptual, experimental, and applied settings are discussed.
Journal of the Experimental Analysis of Behavior, 2026 · doi:10.1002/jeab.70082