Association for Behavior Analysis International

The Association for Behavior Analysis International® (ABAI) is a nonprofit membership organization with the mission to contribute to the well-being of society by developing, enhancing, and supporting the growth and vitality of the science of behavior analysis through research, education, and practice.


33rd Annual Convention; San Diego, CA; 2007

Event Details

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Symposium #197
What Stimuli Comprise an Equivalence Class?
Sunday, May 27, 2007
10:30 AM–11:50 AM
Del Mar AB
Area: EAB/TPC; Domain: Basic Research
Chair: Karen M. Lionello-DeNolf (University of Massachusetts Medical School, E.K. Shriver Center)
Discussant: Caio F. Miguel (California State University, Sacramento)
Abstract: Sidman (2000, JEAB) suggested that class-specific outcomes and responses can become members of an equivalence class. This symposium will discuss that issue and present data from work with pigeons, typically developing adults, and students with developmental disabilities. Urcuioli and Vasconcelos tested for acquired equivalence between sample stimuli after pigeons were trained on many-to-one matching. Their data suggest that determining whether responses become part of the class is not straightforward. Using a procedure developed to use defined responses as samples in a matching task (Lionello-DeNolf & Urcuioli, 2003; JEAB), Braga-Kenyon and Lionello-DeNolf provide mixed evidence that responses become members of a class. After training, at least 2 adults passed some tests for class membership, but failed others. Finally, Shimizu trained developmentally disabled students using a differential outcomes procedure in which correct choices in a matching task were followed by the presentation of a third stimulus prior to reinforcement. His data suggest a more efficient training method for applied settings in which equivalence develops after training on 1 conditional discrimination rather than the typical 2. These data provide mixed support for Sidman’s assertions. While class-specific outcomes were shown to become class members, the same was true for responses only under certain conditions.
Within-Class Differences in Sample Responding Can Preclude Acquired Sample Equivalence Pigeons’ Many-to-One Matching.
PETER URCUIOLI (Purdue University), Marco Vasconcelos (Purdue University)
Abstract: Pigeons do not show an acquired equivalence between a sample stimulus consisting of a particular pattern of responding and a visual sample even though both occasion the same, reinforced comparison choice (Urcuioli et al., JEAB, 2006). Unlike other many-to-one training procedures, however, this paradigm also requires pigeons to respond differently to the samples within each common-comparison class. If this within-class difference is responsible for the lack of acquired equivalence, acquired equivalence should also fail develop between visual sample stimuli that occasion the same reinforced choice if their associated sample-response requirements differ. I will present results that confirm this prediction along with other results showing that different arrangements of within- versus between-class sample-response contingencies can produce acquired equivalence-like effects. The data indicate that testing for response membership in acquired equivalence classes is not a straightforward proposition, at least with pigeons.
Inclusion of Differential Responses in Equivalence Classes.
PAULA RIBEIRO BRAGA-KENYON (New England Center for Children), Karen M. Lionello-DeNolf (University of Massachusetts Medical School, E.K. Shriver Center)
Abstract: We investigated whether differential responses to stimuli can become members of an equivalence class. Adult participants were trained on a computer touch screen to make 2 distinct responses (FR and DRL) to color stimuli. Then, they were trained to match form stimuli to color comparisons with a common response (FR 1) to all stimuli. Finally, participants were taught to make both responses to a single (white square) stimulus in a modified mixed-schedule task (cf. Lionello-DeNolf & Urcuioli, 2003; Urcuioli et al., 2006, JEAB). This procedure allows DRL and FR responses to serve as samples in a matching task without the addition of differential exteroceptive stimuli. Participants were given 3 tests to determine class membership; no reinforcement was given in test. Test 1 presented the form stimuli; responses were recorded and categorized as either class-consistent or class-inconsistent. Tests 2 and 3 presented DRL and FR as samples followed by either form or color comparisons, respectively. Preliminary data from 2 participants indicate high class-consistent responding (80 – 100%) on matching tests and mixed results on form – response tests. These data provide evidence for the inclusion of responses in equivalence classes.
How to Apply Basic Finding of Equivalence Research to Instructional Design?
Abstract: Ideas to apply equivalence technology to instructional design will be discussed by first describing findings using a differential outcomes training procedure and then by presenting applications of the procedure and by showing data from an ongoing project design to build vocabulary. While there is much basic research about equivalence, applications of those findings are rare. When scientific technology becomes widespread, procedures are efficient and easy to be implemented, and users don’t even notice the use of the technology. One way to apply equivalence technology to applied settings is a differential outcome procedure. Here, a subject learns to select stimulus B conditionally upon stimulus A. Right after the selection and before the delivery of a reinforcer, stimulus C is presented as a differential outcome. Stimulus C is a neutral stimulus and doesn’t serve any function including a conditional discriminative stimulus, discriminative stimulus, or reinforcer. Typically, subjects are required to learn two conditional discriminations (AB and BC) to establish equivalence classes. Using the differential outcome procedure, it may be possible to train just one discrimination if the differential outcomes (the C stimuli) join the equivalence classes. If this is true, the theory would help us to design efficient instruction.



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