A Normative Model for Redundancy Gains in Speech Discrimination
This chapter provides a detailed examination of the processes that underlie such redundancy gains in speech discrimination. It presents a brief review of redundancy gains in multidimensional discrimination experiments and outlines several process models that have been proposed to account for such results. The chapter describes a normative model that enables the magnitude of the redundancy gain and the form of the redundant-dimension Response time (RT) distribution to be predicted from empirical RT distributions for single dimensions. It aims to compare the empirical redundancy gains obtained for auditory and phonetic dimensions to those predicted by the normative model. Empirical support for the general distinction between auditory and phonetic processes has been obtained in a number of different experimental paradigms. A model based on holistic processing has been proposed by Lockhead to account for redundancy gains with integral dimensions in both accuracy and RT data.