Stimulus equivalence: A conceptual and empirical investigation of generalizations of abstract stimuli: Does proximity equal equivalence?

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OsloMet - storbyuniversitetet. Institutt for atferdsvitenskap

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Master i læring i komplekse systemer


Stimulus equivalence can be defined as emergence of new relations without direct reinforcement after conditional discrimination is established, as these new relations can be described by reflexivity, symmetry, and transitivity. Such relations are said to represent “sameness” of the stimuli, despite having different topographies. The nodal distance hypothesis is a hypothesis about stimulus equivalence whereas responding in accordance with emergent conditional discrimination decreases as a function of increasing numbers of nodes. A node is a stimulus that “connects” responding in accordance with two or more conditional discriminations and occasions for transitivity relations. For instance, one can establish conditional discrimination by differential reinforcement of the relations AB, BC, and CD, as this may lead to the occurrence of new relations AC and AD. The AC relation has B stimulus as one node and the AD relation has stimulus B and C as nodes. The AC relation is a 1-node relation and the AD relation is a 2-node relation. The prediction of the hypothesis is that responding in accordance with AC relations occurs with larger probability than AD relations. Article I in this paper investigated conceptual issues regarding the hypothesis. This was done by investigating common philosophical assumptions of different forms of behaviorisms and different behavioristic positions to reinterpret the nodal distance hypothesis. Article II investigated empirical issues regarding the hypothesis. This was done by investigating how several measurements of responding in accordance with new relations are changed by number of nodes.




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