Norwegian version

Public defence: Vanessa Ayres Pereira

Vanessa Ayres Pereira will defend her thesis "Emergence of Large Equivalence Classes as a Function of Different Training Structures" for the PhD in Behavior Analysis.

Trial lecture title: The role of theory in behavior-analytic philosophy of science and experimental design.

Th ordinary opponents are:

The leader of the public defence is Professor Ingunn Sandaker, OsloMet.

The main supervisor is Professor Erik Arntzen, OsloMet. The co-supervisor is Torunn Lian, OsloMet.

Thesis abstract

This thesis is composed of three experiments designed to verify predictions of the Discrimination-Analysis (DA) hypothesis about the effectiveness of the Many-to-One (MTO) and One-to-Many (OTM) training structures in producing equivalence classes.

In the MTO training structure, the baseline relations are interrelated by a common comparison stimulus and in the OTM, they are interrelated by a common sample. The "common" stimulus is called node.

Experiment 1

Experiment 1 verified whether mixing baseline trials among emergent test trials would enhance the yields of emergence of three 5-member classes following the OTM training structure. Twenty adults were exposed to two conditions:

  • Simultaneous Protocol with Baseline trials Intermixed (MixB)
  • With Post-test of Baseline trials

Condition MixB had little (and negative) effect on the yields of immediate emergence (that is, on the number of participants who responded in accordance with equivalence).

Experiments 2 and 3

Experiments 2 and 3 verified whether the MTO would be more effective than the OTM to produce the emergence of three 7- and 9-member classes, respectively.

Thirty-four adults participated in Experiment 2 and 42 participated in Experiment 3. Half of them were exposed to the MTO and another half to the OTM.

In Experiment 2, 88 percent of the participants passed the test for emergent relations in both groups. In Experiment 3, 86 percent and 48 percent passed the test in the MTO and OTM groups, respectively.

The second objective of Experiments 2 and 3 was to identify baseline performances predictive of success or failure in the test. In both experiments, the requirement of a great amount of trials to learn the MTO baseline was predictive of failure.

In the OTM group in Experiment 3, the data showed that differences in the frequency of selection of the comparisons, that led to discrepancies in the overall number of reinforcements per node, was predictive of failure.