Extrinsic Uncertainty and Summation Revisited

Norma van Surdam Graham

in Visual Pattern Analyzers

Published in print December 1989 | ISBN: 9780195051544
Published online January 2008 | e-ISBN: 9780199872183 | DOI:

Series: Oxford Psychology Series

 Extrinsic Uncertainty and Summation Revisited

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This chapter considers the uncertainty arising from sources extrinsic to the observer, in particular from the observer's ignorance on any given trial as to which of several alternative stimuli will be presented. Explanations based on multiple independent analyzers are presented, and their predictions for uncertainty experiments and summation experiments are calculated. These models differ in their assumptions about the probability distribution characterizing each analyzer's output and in their assumptions about how the multiple analyzer's outputs are combined to form the observer's decision rule. Several generalization are presented, e.g., probability distributions predicting shallower ROC slopes predict larger blocked-summation effects but smaller uncertainty effects. Further, these models provide some insight into and justification for the quick nonlinear pooling model presented in Chapter 4.

Keywords: multidimensional signal detection theory; attention; decision rule; ROC curves; mathematical models; quick pooling model

Chapter.  14859 words.  Illustrated.

Subjects: Neuropsychology

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