Effect of observing response requirements to sample and comparison stimuli on the establishment of reject control (sample/S‐ relations)
Never block the correct comparison during equivalence training—it creates reject-control errors instead of true classes.
01Research in Context
What this study did
Perez et al. (2020) asked college students to learn three new equivalence classes.
Each trial showed one sample and three comparisons.
Half the time the computer blocked the correct comparison for 3 seconds.
The team then tested if the students could still match new pairs they had never seen.
What they found
Blocking the right answer hurt learning.
Students made more errors on tests of transitivity, equivalence, and reflexivity.
Symmetry stayed fine.
The blocked trials created reject-control errors instead of true class formation.
How this fits with other research
Arntzen et al. (2018) got a large share success by adding pictures and a 6-second delay.
Perez shows the opposite: blocking the correct picture drops success.
Together they tell us timing and access matter more than the pictures themselves.
Lantaya et al. (2018) used a simpler go/no-go format and still got clean classes.
Their work suggests you can avoid Perez's problem by not using the three-array format at all.
Tullis et al. (2021) worked with autistic kids and added instructive feedback.
They let kids see every comparison, matching Perez's advice to never block the right choice.
Why it matters
When you run matching-to-sample, always let the learner see the correct comparison.
If you must use delays, keep them short and never hide the right answer.
This one change can save hours of re-teaching later.
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02At a glance
03Original abstract
The establishment of sample/S- relations (or reject control) during conditional discrimination training (AB, BC) affects transitivity (AC), equivalence (CA) and reflexivity (AA, BB, CC) test outcomes. The present study parametrically evaluated the effects of different observing patterns to comparison stimuli on the establishment of reject control during baseline conditional relation training. A matching-to-sample with observing requirements (MTS-OR) procedure was implemented during AB and BC conditional discrimination training. During training, the participants were required to observe the sample and incorrect comparison on every trial before responding. In addition, the participants were divided into three groups that differed regarding the percentage of training trials on which they were prevented from observing the correct comparison stimuli: 25%, 50%, and 75%. Once the mastery criteria were achieved during training, transitivity (AC), symmetry (BA, CB), equivalence (CA), and reflexivity (AA, BB, CC) tests were conducted with all comparison stimuli visible from the beginning. The results suggest that the number of errors during transitivity, equivalence, and reflexivity tests progressively increased as participants were prevented from observing the correct comparison on a greater number of trials during training. Symmetry test results, however, were not affected by the experimental manipulation. Moreover, the number of participants showing reject-control patterns during tests slightly increased and the number of participants showing select-control patterns decreased as a function of the number of trials on which the participants were prevented from observing the correct comparison. Thus, we suggest that observing patterns during training is a relevant variable that affects equivalence test outcomes.
Journal of the Experimental Analysis of Behavior, 2020 · doi:10.1002/jeab.602