Comparisons of some learning models for response bias in signal detection

Abstract

The effects of variations in signal probability and varying degrees of correct feedback on response bias were studied in a yes-no auditory signal detection task. The main finding was that the bias towards saying yes was an increasing function of the frequency of signal feedback events, but did not depend on the correctness of the feedback. Several learning models coupled with a simple psychophysical and decision model yielded predictions about overall biases and certain sequential statistics. Only one model, which can be decribed as an “informational” model, gave a good account of both observed overall biases and sequential statistics. This model assumes the observer’s response bias is strengthened for the feedback-reinforced response when the observer’s sensory information is ambiguous or is contradicted by the feedback information.