, Volume 22, Issue 4, pp 325–345 | Cite as

Stimulus and response generalization: A stochastic model relating generalization to distance in psychological space

  • Roger N. Shepard


A mathematical model is developed in an attempt to relate errors in multiple stimulus-response situations to psychological inter-stimulus and inter response distances. The fundamental assumptions are (a) that the stimulus and response confusions go on independently of each other, (b) that the probability of a stimulus confusion is an exponential decay function of the psychological distance between the stimuli, and (c) that the probability of a response confusion is an exponential decay function of the psychological distance between the responses. The problem of the operational definition of psychological distance is considered in some detail.


Mathematical Model Public Policy Stochastic Model Statistical Theory Exponential Decay 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Psychometric Society 1957

Authors and Affiliations

  • Roger N. Shepard
    • 1
  1. 1.Naval Research LaboratoryUSA

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